Sponsor Message:
Military Aviation & Space Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
KC-135 Crash In Kyrgyzstan  
User currently offlinezeke From Hong Kong, joined Dec 2006, 9210 posts, RR: 76
Posted (1 year 6 months 4 weeks 1 day 15 hours ago) and read 32767 times:

News reports in of a KC-135 breaking up in flight after takeoff

"US tanker aircraft KC-135 lost contact with ground control immediately after take-off - Kyrgyz Ministry of Emergencies. Bishkek. KC-135 Tanker Aircraft from the Transit Center at Manas lost contact with the Center immediately after take-off, according to preliminary reports received by the Kyrgyz Ministry of Emergencies."

Only reports in Russian at this stage. http://kg.akipress.org/news:574036

BBC has now picked up the story

http://www.bbc.co.uk/news/world-asia-22397266
http://inserbia.info/news/2013/05/ky...hed-near-the-kyrgyz-kazakh-border/
http://www.boston.com/news/world/eur.../viBOhQFueXWqDCkOY0Xs3I/story.html

From the AFP wires :

""According to my information, the plane broke up into three pieces. Information on the dead or wounded is being clarified. All the rescue services have gone to the scene," the ministry's press secretary Abdisharip Bekilov said."

"The emergency situations ministry said that preliminary information was that a KC-135 Stratotanker plane lost contact with the base as soon as it took off.

Witnesses told the Kyrgyz AKIPress news agency that they heard a boom and then an explosion and that the plane was continuing to burn."

Edit to add links

[Edited 2013-05-03 03:45:00]


We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
152 replies: All unread, showing first 25:
 
User currently offlinecjg225 From United States of America, joined Feb 2013, 873 posts, RR: 0
Reply 1, posted (1 year 6 months 4 weeks 1 day 13 hours ago) and read 32767 times:

Jeez.

RIP to the crew, assuming they perished, which sounds likely just from what is known now...



Restoring Penn State's transportation heritage...
User currently offlinezeke From Hong Kong, joined Dec 2006, 9210 posts, RR: 76
Reply 2, posted (1 year 6 months 4 weeks 1 day 12 hours ago) and read 32767 times:

This is the KC-135R being reported in Russian media as the missing aircraft, I believe the aircraft was with the 22nd ARW based at McConnell AFB, Kansas.


View Large View Medium
Click here for bigger photo!

Photo © Matthew C. Lyons



source : http://www.kabar.kg/kyr/inced/full/43348



We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
User currently offlineRevelation From United States of America, joined Feb 2005, 12856 posts, RR: 25
Reply 3, posted (1 year 6 months 4 weeks 1 day 12 hours ago) and read 32767 times:

Sad news. My sympathies to the families.


Inspiration, move me brightly!
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 4, posted (1 year 6 months 4 weeks 1 day 12 hours ago) and read 32767 times:

Yahoo is reporting an apparent parachute jump for the tanker prior to the "explosion".

http://uk.news.yahoo.com/plane-us-ai...kyrgyzstan-ministry-093048852.html

If this is true, then some or all of the crew might have bailed out. Bail out on the KC-135 is through the crew entry chute near the nose landing gear. It also means the crew might have possible radioed they were bailing out, and possible the reason why.

If there was an inflight explosion, the most likely reason could be a fire within the tanker, or even possibly the cargo, if it was carrying any cargo. If a bail out did happen, that would indicate there was only the crew aboard and no passengers.

I am hoping the crew did bail out before the crash. I also know that most aircraft crash witnesses report an inflight break-up and/or explosion, which later turn out to be not true. This does not mean anyone is lying, they just report what they believe they have seen.

I am hoping the crew will be found alive and with not to many injuries. If the crew did not have time to attach the survival seat kit to their parachute harnesses, that is still not a problem in finding the crew. USAF parachutes are equipped with an emergency beacon that begins transmitting as soon as the parachute opens, and continues to transmit until it is manually turned off or the battery dies.


User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 5, posted (1 year 6 months 4 weeks 1 day 12 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

May God be with their families and friends!

KC-135 Crash In Kyrgyzstan (by zeke May 3 2013 in Military Aviation & Space Flight)

http://www.fightercontrol.co.uk/forum/viewtopic.php?f=287&p=493663

http://rss.rt.com/news/us-plane-crashes-kyrgyzstan-771/

     

VERY SADLY...
135Mech


User currently offlinezeke From Hong Kong, joined Dec 2006, 9210 posts, RR: 76
Reply 6, posted (1 year 6 months 4 weeks 1 day 11 hours ago) and read 32767 times:

Photos of the missing airframe (from http://kg.akipress.org/news:574074)

http://www.ljplus.ru/img4/g/o/gogiman/135e9c3899712386b7d6d6b68a6ac72a.jpg


Photos of the crash area

http://kg.akipress.org/news:574061

Photos of the aircraft pieces

http://kg.akipress.org/news:574074

Video of the crash area

http://kg.akipress.org/news:574076



We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 7, posted (1 year 6 months 4 weeks 1 day 11 hours ago) and read 32767 times:

KC-135s rarely carry parachutes unless they're doing a functional checkflight, like after the plane's been put back together after a major PDM/depot trip. For those of you who don't know how it works, there is an escape spoiler that is extended with an air bottle and it is supposed to block the slipstream in front of the crew entry hatch. I don't think it's really a viable option though, as you'd likely end up going into the #2 engine, hitting the wing, or richocheting across the fuselage. The escape spoiler emergency air bottle is not serviced on the aircraft unless parachutes are going to be carried, again I have never seen them onboard.

Real shame to lose a KC-135 like this, I am sure the crew did their best to save the plane. The spooky thing is, if this is the plane that went down, I worked on this plane a lot at Al Udeid last year. I remember the tail number (8877) very well because it had a lot of maintenance issues and we were always working on it.


User currently offlinevenus6971 From United States of America, joined Dec 2004, 1443 posts, RR: 0
Reply 8, posted (1 year 6 months 4 weeks 1 day 11 hours ago) and read 32767 times:

Quoting KC135TopBoom (Reply 4):

Hey Boom, they took off the parachutes years ago to save weight and only service the bailout chute spoiler only when they do test flights. Still have some friends who are mx and ops and nobody is talking. Been a tough week the NAC bird was also one I have taken care of and knew the crew also. I wonder if turbulance coming off the Tien Shen Mtns had anything to do with this.



I would help you but it is not in the contract
User currently offlinecargotanker From United States of America, joined Oct 2009, 164 posts, RR: 1
Reply 9, posted (1 year 6 months 4 weeks 1 day 11 hours ago) and read 32767 times:

Quoting KC135TopBoom (Reply 4):
Yahoo is reporting an apparent parachute jump for the tanker prior to the "explosion".

So much of that Yahoo story is odd, (tires are still on fire, schoolchildren filmed it) but an inflight bailout would be remarkable. Here's hoping... Other sites are saying five crew, no survivors.


User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 10, posted (1 year 6 months 4 weeks 1 day 11 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Quoting venus6971 (Reply 8):
Quoting KC135TopBoom (Reply 4):


Hey Boom, they took off the parachutes years ago to save weight and only service the bailout chute spoiler only when they do test flights. Still have some friends who are mx and ops and nobody is talking. Been a tough week the NAC bird was also one I have taken care of and knew the crew also. I wonder if turbulance coming off the Tien Shen Mtns had anything to do with this.

Last I knew (when I was still working them) the Parachutes were installed for any overwater missions and deployments, but yes, at homestation they are removed for weight etc. Also, the escape bottles are not kept up to the service limit anymore. Maybe this will put that all back into use?

135Mech


User currently offlinezeke From Hong Kong, joined Dec 2006, 9210 posts, RR: 76
Reply 11, posted (1 year 6 months 4 weeks 1 day 11 hours ago) and read 32767 times:

Quoting cargotanker (Reply 9):
tires are still on fire

That is visible in the photos




We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 12, posted (1 year 6 months 4 weeks 1 day 10 hours ago) and read 32767 times:

From the photos, which were taken shortly after the crash, it does not appear that weather was a factor.

Quoting venus6971 (Reply 8):
I wonder if turbulance coming off the Tien Shen Mtns had anything to do with this.

Good question, but the Tien Shen Mountains abut the Chinese border, and the airplane would have to have been well off course to stray that close to them to encounter CAT.

I tend to discount the report of parachutes. They are not worn, but are stowed (beginning in the 1990s their primary use is to enable the boomer to check overwing and rear hatches during flight). The amount of time it would take for someone to unbuckle from a seat, move to the cargo cabin, collect and don the parachute (assuming they knew where it was and how to put it on), move back to the cockpit, pop the spoiler (again, assuming they knew how), and egress is not consistent with an uncontrolled bail out.

Quoting KC135Hydraulics (Reply 7):
you'd likely end up going into the #2 engine, hitting the wing, or richocheting across the fuselage. The escape spoiler emergency air bottle is not serviced on the aircraft unless parachutes are going to be carried, again I have never seen them onboard.

Before they took the parachutes out of the RC-135 we always morbidly joked that the lowest ranking person would bail out first because their body would clean off most of the MUCEL antennas and all the other crap under the fuselage, then the rest of the crew could bail out safely.

My daughter lives in Kyrgyzstan, and will continue to send updates and translations of Russian and Kyrgyz articles (for those of us who don't read those languages).


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 13, posted (1 year 6 months 4 weeks 1 day 9 hours ago) and read 32767 times:

Prior to today, there was at least two successful bailouts from the KC-135. One during flight testing back in 1956, there is a video of this somewhere, and the second one where a Boom Operator bailed out (without approval by the pilot) when he was thinking the airplane would crash.

AIUSI, parachutes are still used today on the KC-135 during combat missions in case of a MANPAD attack.

The way the crew entry chute bail-out system worked (normally the pilot would manually depressurize the airplane by ejecting a fuselage plug in the cargo compartment, he has a "T" handle on his instrument panel) and the Boom Operator would activate the chute by pulling down a handle bar over the chute. This would deploy the spoiler, which extended about 4' below the entry chute. As the spoiler deployed, it would kick the entry chute door off its hinges into the slipstream and fall away. As long as the airspeed was above about 150 KIAS the crew members would fall away from the airplane in about a 30 to 45 degree angle (depending on airspeed) and clear the airplane, going under it.


User currently offlinethreeifbyair From United States of America, joined Aug 2007, 705 posts, RR: 1
Reply 14, posted (1 year 6 months 4 weeks 1 day 9 hours ago) and read 32767 times:

Quoting zeke (Reply 2):
This is the KC-135R being reported in Russian media as the missing aircraft, I believe the aircraft was with the 22nd ARW based at McConnell AFB, Kansas.

Pictures on Twitter clearly show "ONNELL" on the tail so that would be consistent with it being a McConnell aircraft.


User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 15, posted (1 year 6 months 4 weeks 1 day 8 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Quoting rc135x (Reply 12):
My daughter lives in Kyrgyzstan, and will continue to send updates and translations of Russian and Kyrgyz articles (for those of us who don't read those languages).

Thank you for all of your inputs! This just sucks!

135Mech


User currently offlineAesma From France, joined Nov 2009, 6845 posts, RR: 12
Reply 16, posted (1 year 6 months 4 weeks 1 day 7 hours ago) and read 32767 times:

Quoting KC135TopBoom (Reply 13):
As long as the airspeed was above about 150 KIAS the crew members would fall away from the airplane in about a 30 to 45 degree angle (depending on airspeed) and clear the airplane, going under it.

Why would a higher airspeed be better, attitude of the airplane ? I'm a skydiver and pilots slow down before we jump.



New Technology is the name we give to stuff that doesn't work yet. Douglas Adams
User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 17, posted (1 year 6 months 4 weeks 1 day 7 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Quoting Aesma (Reply 16):
Why would a higher airspeed be better, attitude of the airplane ? I'm a skydiver and pilots slow down before we jump.

When you jump (out of the turbo prop planes for parachting), one reason your pilot slows down is so that your body can get clear of the plane, and not have severe winds catching you before the actual dropping. The KC-135's with their 35 degree swept wing, slowing to 150KIAS is 'slow' for them, any (significantly) slower and they would not sustain their needed lift. Much faster than the 150KIAS and you would risk going to fast for the person to drop far enough, fast enough, to clear the landing gear (if extended), inboard flaps (to include the fillet flap), and wign to body fairing.

Hope this answers your question.

Regards,
135Mech


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 18, posted (1 year 6 months 4 weeks 1 day 7 hours ago) and read 32767 times:

Quoting Aesma (Reply 16):
Why would a higher airspeed be better, attitude of the airplane ? I'm a skydiver and pilots slow down before we jump.

In flight, depending on the gross weight, the KC-135 cannot slow to below 150 KIAS, or so. Typical landing speeds are around 140 KIAS.

The idea is to get away from the airplane as quickly as possible. The bail out procedure (IIRC) was to pull the green apple to give you oxygen, then hang by your arms on the bar that deployed the spoiler, then pull your knees up to your chest and upon letting go you brought your arms across your chest and grab the harness on the opposite side from your arm. This put you into a sort of 'ball' as you fell from the airplane and you would roll due to the slipstream. As soon as you were clear of the airplane, you pulled the other 'apple' to start the auto chute deployment, once you got down to 14,000', or if below 14,000' pull the "T" handle (sometimes it was a "D" ring) to deploy your chute.

IIRC, we were not to try to position ourselves like a skydiver, unless we were trained for that. Instead we assumed an "attention" position until chute deployment. This may cause some spinning, but it should not be enough to get tangled in the raisers and lines during deployment.

I am still hoping for the crew, even though I know it looks bad.

Farewell 63-8877, old friend.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 19, posted (1 year 6 months 4 weeks 1 day 6 hours ago) and read 32767 times:

It's so surreal to know that the plane I was working just a few months ago is now gone under such circumstances.

User currently offlinerfields5421 From United States of America, joined Jul 2007, 7607 posts, RR: 32
Reply 20, posted (1 year 6 months 4 weeks 1 day 5 hours ago) and read 32767 times:

Quoting KC135TopBoom (Reply 18):
This put you into a sort of 'ball' as you fell from the airplane

In September 1973 my squadron had a crew bail out of an EA-3B Skywarrior (similar to the USAF RB-66). Fuel starvation after getting lost between Guam and Subic.

The aircraft has a door which drops down behind the nose gear. They slid down the ramp into the aircraft slipstream.

All five people were knocked silly and woke up in their chutes before landing. All five had their face shields broken and two guys had parts of the face shield impeded in the front of their boots. They all has strained hip joints.

That bailout was setup at 155 kts at 10,000 ft with the plane on autopilot.


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 21, posted (1 year 6 months 4 weeks 1 day 4 hours ago) and read 32767 times:

Quoting 135mech (Reply 17):
Much faster than the 150KIAS and you would risk going to fast for the person to drop far enough, fast enough, to clear the landing gear (if extended), inboard flaps (to include the fillet flap), and wign to body fairing.

The 'secondary' bail-out exit is the aft hatch. You are not suppose to bail out through the crew entry chute if gear, flaps, or Boom are extended.


User currently offlineflyingturtle From Switzerland, joined Oct 2011, 2456 posts, RR: 14
Reply 22, posted (1 year 6 months 4 weeks 1 day 2 hours ago) and read 32767 times:

What does this suggest?

Until now we've debated a possible escape from the KC-135, and one would need stable flight (and therefore, a reasonably intact airplane) to use an bailout chute.


http://static.akipress.org/127/.storage/news/images/2013May/8845b86c69c29b40422288f80e3890ae.jpg

My not-very-educated guess is a inflight breakup...  


David



Keeping calm is terrorism against those who want to live in fear.
User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 23, posted (1 year 6 months 4 weeks 1 day 2 hours ago) and read 32767 times:

Quoting flyingturtle (Reply 22):
What does this suggest?

Two widely separated impact points may well mean something like in-flight fuselage failure form whatever cause at the wing junction causing two large sections of the airframe to come down far apart. As both are burning, both likely would have had a lot of fuel, perhaps ruling out separation at the empennage. Or perhaps a wing broke off and the remainder spun in nearby. Either way it appears to have happened at a low altitude given the close proximity of the two major impact sites.

Edit: correct typographic error

[Edited 2013-05-03 16:21:19]

User currently offlineTankereng From United States of America, joined Feb 2013, 27 posts, RR: 0
Reply 24, posted (1 year 6 months 4 weeks 1 day 1 hour ago) and read 32767 times:

Heard about it this morning when I got to work. Very tragic.

From the pictures it looked like the gear were retracted. It does look like it could be an inflight breakup. I wonder if one of the terminal fittings failed.

Never got to see 8877 in person at Tinker. Last PDM was at San Antonio.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 25, posted (1 year 6 months 4 weeks 1 day 1 hour ago) and read 32767 times:

I saw a picture on Fox News today that showed the vertical stabilizer lying on the ground by itself, missing a rudder, but with a small portion of attached fuselage at the bottom. That to me indicates an inflight breakup, as there is no debris around it and it has absolutely no fire damage.

User currently offlinezeke From Hong Kong, joined Dec 2006, 9210 posts, RR: 76
Reply 26, posted (1 year 6 months 4 weeks 1 day ago) and read 32767 times:

Quoting KC135Hydraulics (Reply 25):

Initial reports were the aircraft broke up into 3 pieces in flight with an explosion. The picture in reply 22 would indicate 2 impact locations, and the one you saw on fox the third possibly.



We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 27, posted (1 year 6 months 4 weeks 1 day ago) and read 32767 times:

Here is a link to the story on Fox News, the photo should be available there:

http://www.foxnews.com/world/2013/05...hes-in-kyrgyzstan/?test=latestnews


User currently offlineGonzalo From Chile, joined Aug 2005, 1994 posts, RR: 2
Reply 28, posted (1 year 6 months 4 weeks 22 hours ago) and read 32767 times:

What a horrible week for aviators... I apologize for being so pessimistic, but I think there is enough evidence of a sudden in-flight break up and, therefore, no one was able to escape from the aircraft. And the place where this happened, although seems to be a rural / not very populated area, is not a deserted place, and a crewman hanging from a parachute should be an easy target for all the spotters around.

My respects to the victims and their families.

Rgds.
G.



80 Knots...V1...Rotate...Gear Up...DC-3 / EMB-110 / Fairchild-227 / Ab318-19-20 / B732 / B763
User currently offlineawacsooner From United States of America, joined Jan 2008, 1950 posts, RR: 1
Reply 29, posted (1 year 6 months 4 weeks 17 hours ago) and read 32767 times:

Sounds like the crew was a SKA crew...

User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 30, posted (1 year 6 months 4 weeks 13 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Wow! This just keeps getting worse! Thank you all for being so awesome with you comments and respects for our fallen Airmen!

And, yes, I did forget to mention using the aft hatch as the hopeful exit point when gear/flaps are down.

KCHydraulics, it's amazingly sad when those realities hit us, I know and it's horrible!

Regards,
135Mech


User currently onlinemoose135 From United States of America, joined Oct 2004, 2382 posts, RR: 10
Reply 31, posted (1 year 6 months 4 weeks 13 hours ago) and read 32767 times:

Kyrgyz officials announced that the remains of two crew members have been found. RIP to my fellow tanker buddies.


KC-135 - Passing gas and taking names!
User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 32, posted (1 year 6 months 4 weeks 13 hours ago) and read 32767 times:

There have been three previous inflight explosions on the KC-135 plus a fourth on the ground that I can remember but the last was some twenty years ago. When they converted all of the airframes away from the J-57 the accident rate has almost stopped..


OMG-Obama Must Go
User currently offlinezanl188 From United States of America, joined Oct 2006, 3566 posts, RR: 0
Reply 33, posted (1 year 6 months 4 weeks 13 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Pix I have seen indicate seperate impact points for at least two engines (cratered), vert stab, the boom, and a wing section.

Catastrophic whatever it was...



Legal considerations provided by: Dewey, Cheatum, and Howe
User currently offlinevenus6971 From United States of America, joined Dec 2004, 1443 posts, RR: 0
Reply 34, posted (1 year 6 months 4 weeks 12 hours ago) and read 32767 times:

If it was a inflight explosion such as a ACM shelling or a AR pump or center wing boost pump letting go the USAF will be looking hard at all safety of flight components that if fail inflight can cause this type of disaster. Being a 23 year vet and doing the contracting thing I can tell you that all the rebuilt parts we get are not much better than the defective ones we replace. If this jet exploded in mid air I am guessing something like that TWA 747 that blew up on climb out out of JFK a few years back. Exposed wires and fuel fumes, another note to think about we don't use JP-8 in Manas, we use its Russian mix TS-1? When we switched from JP-4 to JP-8 we stopped for a awhile having -135's explode, just wondering about the fuel mix.


I would help you but it is not in the contract
User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 35, posted (1 year 6 months 4 weeks 12 hours ago) and read 32767 times:

The 135's also stopped exploding inflight after they installed the low pressure lights for the fwd and aft body boost pumps after the last one at Loring.


OMG-Obama Must Go
User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 36, posted (1 year 6 months 4 weeks 12 hours ago) and read 32767 times:

Quoting windy95 (Reply 32):
There have been three previous inflight explosions on the KC-135 plus a fourth on the ground that I can remember but the last was some twenty years ago. When they converted all of the airframes away from the J-57 the accident rate has almost stopped..

KC-135A 58-0031 19 Mar 82
KC-135A 60-0330 13 Feb 87
KC-135E 57-1481 20 Sep 89
KC-135A 56-3592 4 Oct 89
KC-135R 57-1470 10 Dec 93

Cause of loss: overheated body tank fuel pump.


User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 37, posted (1 year 6 months 4 weeks 11 hours ago) and read 32767 times:

The R model in 1993 was at Mitchell Field and it was caused by the Center tank pump and the E model at Eielsen was the APU. There have been four inflight explosions that have possible links to the over heating of the Hydraulic boost pumps. The three you have above that happened in the 80's plus another that happened in Spain in the early 70's.


OMG-Obama Must Go
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 38, posted (1 year 6 months 4 weeks 10 hours ago) and read 32767 times:

Quoting flyingturtle (Reply 22):
My not-very-educated guess is a inflight breakup...

That could be because of a lot of reasons from structural failure, MANPAD or other anti-aircraft system, to a fuel explosion of some type, to extreme turbulence or mountain wave.

Quoting windy95 (Reply 32):
There have been three previous inflight explosions on the KC-135 plus a fourth on the ground that I can remember but the last was some twenty years ago. When they converted all of the airframes away from the J-57 the accident rate has almost stopped..

None of them had anything to do with the type of engines. As RC135x pointed out, the fuel system explosions caused by the body tank AR pumps have happened on the "A", "E", and "R" models. In addition to that, back in the '60s or '70s a KC-135Q wingtip blew off due to a short circuit of a wingtip strobe light (the "Q" was one of the first aircraft to be equipped with strobe lights and each wingtip had two of them, one on the upper skin and one on the lower skin as well as one each on the upper and lower fuselage and the tail) and a minor fuel leak in the wingtip reserve fuel tank.

Shelling of the ACM should not cause a break-up, but will damage the airplane. Although if a fuel tank is punched (it would be either or both the #2 main wing tank and/or the center wing tank) by the ACM turbine blades and the heat exchanger was hot enough that it might cause an explosion. I have never heard of this actually happening.

63-8877 was going on an air refueling mission over Afghanistan, so the fuel pumps should have been submerged in fuel. Even if they were running with the switching off, the fuel would have kept the pumps cool. So I doubt that is what caused the break-up. This was a McConnell based airplane flown by a Fairchild based crew, which is not uncommon when deployed.

It has been reported the tanker was flying "low". This would be unusual because they were about 100 miles from UCFM and the KC-135R performance would have put them at or near cruise altitude, even at combat weights. The initial ROC for the "R" model and MTOW is close to 5000 fpm and the crash happened some 20 to 25 minutes after departure.

If the reports of the tanker flying low are true, this could indicate a problem known to the crew and they were working on it. They also would have been talking to Manas via secure UHF radio.

It has been reported that two of the three crewmembers aboard have been found and they are deceased, the third crewmember has not been found. It has been more than 24 hours now since the crash and apparently no word has been heard from the 3rd crewmember. If he bailed-out, they would have still been able to zero in on his parachute ELB, So, it is not looking good for the 3rd man's survival.


User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 39, posted (1 year 6 months 4 weeks 10 hours ago) and read 32767 times:

Quoting KC135TopBoom (Reply 38):
None of them had anything to do with the type of engines.

I never tied the engines to the pump related accidents. I was just stating that once they had been re-engined to the R model that the accident rate had stopped. This is the first R model in flight loss.

Quoting KC135TopBoom (Reply 38):
the fuel system explosions caused by the body tank AR pumps have happened on the "A", "E", and "R" models.

No all three known are A models. The National Guard E and R model losses happened on the ground. The one was at Mitchell Field which was bad wiring on the center wing pump which was the tank that exploded when the mechanic pushed in the popped cirrcuit breaker. The other being the Eielsen tanker which also burned on the ground from the APU fire. No R or E models hav had in-flight explosions attributed to fuel tanks.

The four known in-flight explosions causing total loss

3-Jun-71 58-0039 Q Torrejon Crashed following in-flight explosion of the nr. 1 main fuel tank.

19-Mar-82 58-0031 A Illinois ANG Exploded at 13,500 feet on approach to O’Hare

13-Feb-87 60-0330 A Altus Landed on the runway at Altus afb on final approach had an explosion in the aft body tank.

4-Oct-89 58-3592 A Loring In-flight explosion (aft body tank) during approach

Sorry but no E or R model inflight losses attributed to the Fwd or Aft body fuel pumps.

[Edited 2013-05-04 08:41:57]


OMG-Obama Must Go
User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 40, posted (1 year 6 months 4 weeks 9 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

I have had an ACM shell out in flight, the housing/casing of the impeller is 'overbuilt' to contain any failures, and after digging out the impeller pieces from the heat exchanger,removing everything and searching in depth, there was no external damage whatsoever to any othepart of the acft (thankfully).

Regards,
135Mech


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 41, posted (1 year 6 months 4 weeks 9 hours ago) and read 32767 times:

Quoting 135mech (Reply 40):
I have had an ACM shell out in flight, the housing/casing of the impeller is 'overbuilt' to contain any failures, and after digging out the impeller pieces from the heat exchanger,removing everything and searching in depth, there was no external damage whatsoever to any othepart of the acft (thankfully).

Regards,
135Mech

I've seen one shell out during an engine start because one of the valves that controls bleed air going to it was stuck open. The casing of it was completely shattered (looked like ceramic pieces) and there was some tentacle looking stuff hanging out of it but there was no external damage to the surrounding area that I could see. The electricians had all of it all out and replaced in a shift though of course the aircraft was impounded for a while after.


User currently offlinefsnuffer From United States of America, joined Jun 2007, 252 posts, RR: 0
Reply 42, posted (1 year 6 months 4 weeks 8 hours ago) and read 32767 times:

I am showing my age here, but with a crew of three did they get rid of the navigator position? If so, when?

To the crew, RIP


User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 43, posted (1 year 6 months 4 weeks 7 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Yes sir they did. In the late 90's we installed the upgraded PACER-CRAG 'glass cockpit' and that eliminated the 'Navigators'. Dual GPS, no more INS/DNS etc.

135Mech

P.S. I helped install and mod those, and makes me feel old from using the old round dial fuel gages etc! LOL


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 44, posted (1 year 6 months 4 weeks 7 hours ago) and read 32767 times:

Quoting windy95 (Reply 37):
the E model at Eielsen was the APU.
Quoting windy95 (Reply 39):
The National Guard E and R model losses happened on the ground.

The Alaska ANG KC-135E ground explosion happened just after taxi in from a mission. The two Instructor Boom Operators were killed in the explosion as they went aft to start the APU (Solar type). The APU had not been started, yet, they were opening the two intake and one exhaust ports. The engines had not been shut down yet, and it was the #1 hydraulically powered, electrically controlled AR pump in the Aft Body Tank that overheated and exploded. The Loring accident happened about 3 weeks later and killed the entire crew, including a very good friend of mine. After the Loring accident we had to keep about 3,000 lbs of fuel (IIRC) in the aft body tank to assure the pumps would be cooled.

The electrical cause was traced to the new digital fuel panel with the tiny, hard to see pump switches on both the Loring and Alaska accidents. The Illinois airplane still had the old original fuel panel.


User currently offlineKC135R From United States of America, joined Apr 2005, 728 posts, RR: 4
Reply 45, posted (1 year 6 months 4 weeks 6 hours ago) and read 32767 times:

Quoting windy95 (Reply 35):
The 135's also stopped exploding inflight after they installed the low pressure lights for the fwd and aft body boost pumps

It has been about 5 years since I have touched a KC-135, but unless something has changed, the A/R pumps were replaced/upgraded a few years back and the low pressure lights/shutoff system deactivated. In theory, the new pumps are supposed to be able to run in an empty tank and cause no problems. Now that only applies to the 2 body tanks, so the other 8 tanks could still be a factor.

Sad day in the KC-135 world, and especially here in the Spokane community.


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 46, posted (1 year 6 months 4 weeks 2 hours ago) and read 32767 times:

Quoting KC135R (Reply 45):
Now that only applies to the 2 body tanks, so the other 8 tanks could still be a factor.

Actually, it only applies to 5 tanks, the 4 main wing tanks and the center wing tank. IIRC both reserve tanks and the upper deck tank were gravity flow into other tanks with pumps, only.

Has that changed?

Quoting KC135R (Reply 45):
unless something has changed, the A/R pumps were replaced/upgraded a few years back and the low pressure lights/shutoff system deactivated.

Thanks, I didn't know that, or if I did, I forgot it.

Quoting KC135R (Reply 45):
In theory, the new pumps are supposed to be able to run in an empty tank and cause no problems.

Engineer's theory?


User currently offlineKC135R From United States of America, joined Apr 2005, 728 posts, RR: 4
Reply 47, posted (1 year 6 months 4 weeks 1 hour ago) and read 32767 times:

Quoting KC135TopBoom (Reply 46):
Actually, it only applies to 5 tanks

Yes, good point - I was unintentionally misleading by counting all the tanks that do not have AR pumps while simultaneously forgetting to exclude the 3 tanks that have no pumps.

Quoting KC135TopBoom (Reply 46):
Engineer's theory?

I suppose - it has been a few years and I was a hydro guy not fuels (so I dealt with everything up to the pump, but not the pump itself), but IIRC the old pumps used fuel to lube a bearing. So no fuel and a running pump = heat in a fuel vapor area. In normal ops the pump should have always been submerged, but run the tank dry and forget to turn off the pump and it's a different equation. AFAIK the new pumps have sealed bearings that require no additional lubricant so can run safely regardless of fuel level.


User currently offlineaaron747 From Japan, joined Aug 2003, 8228 posts, RR: 26
Reply 48, posted (1 year 6 months 3 weeks 6 days 18 hours ago) and read 32767 times:

Really sobering image here of the v-stab on its side in pretty good condition, with the rudder missing in its entirety as previously stated. The fin attachment fairing is still intact, which leads me to assume whatever happened was of sufficient force to blow the tail off clean.

Either way, an altogether awful day for the crew, their families, and all in the tanker community.  

[Edited 2013-05-05 00:17:34]


If you need someone to blame / throw a rock in the air / you'll hit someone guilty
User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 49, posted (1 year 6 months 3 weeks 6 days 10 hours ago) and read 32767 times:

There was a TCTO some years back as previously stated that changed the way the pump is lubricated. It is now lubricated with hydraulic fluid instead of fuel. When the shaft seal starts to go bad the overboard drain will leak hydraulic fluid where it used to leak fuel. Our TOs state not to run the A/R pump with less than 2,000lbs in the body tanks, but I think the reason for this is to avoid prolonged cavitation of the pump rather than to avoid overheating. When draining a body tank for maintenance it is routine to run the pump in bursts below 2,000lbs to get as much fuel out of the tank as possible to cut down on the amount of sumping required afterwards.

There is still a low pressure light on the IFMP for each pump but it gets its power/signal from a low pressure switch mounted outside of the tanks and connected to the fuel lines from each pump by a hose. It lights up the light on the IFMP when the pressure falls below a certain level and the pump's associated switch is on.


User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 50, posted (1 year 6 months 3 weeks 6 days 10 hours ago) and read 32767 times:

Quoting KC135TopBoom (Reply 44):
The Alaska ANG KC-135E ground explosion happened just after taxi in from a mission. The two Instructor Boom Operators were killed in the explosion as they went aft to start the APU (Solar type). The APU had not been started, yet, they were opening the two intake and one exhaust ports. The engines had not been shut down yet, and it was the #1 hydraulically powered, electrically controlled AR pump in the Aft Body Tank that overheated and exploded.

Yes. I was the SAC SOF on the ramp and watched this happened. Aside from rescue and fire control efforts, we had to move several other KC-135s adjacent to the accident. Two pilots of the 24th SRS and an ATTF crew chief were decorated for emergency starting and moving a KC-135R next to the burning wreckage, preventing loss of another airframe, somewhat like the crash at Walker AFB, NM, on 3 Feb 60.

I included the Wisconsin R model because it was an explosion in a fuel tank, irrespective of cause or location. I should have been clearer in my example, thanks!

The accident report for the Torrejon KC-135Q crash indicates that the airplane began an instrument approach in moderate weather. Sometime during the approach, investigators believe the airplane suffered a lightning strike on the left wing, causing the #1 wing tank to explode. The aircraft became marginally controllable and flew into the ground.

A brief update from Kyrgyzstan: Even though the crash occurred in a rural area with no domestic impact, it has increased political pressure on the Kyrgyz government to terminate U.S. access to Minas. There is little to no continuing interest in the crash among the general public.


User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 51, posted (1 year 6 months 3 weeks 6 days 8 hours ago) and read 32767 times:

Well I think we have it all covered between us. I think for the Alaska R model accident I was thinking about the E model ground fire we had at Pease which was partly attributed to the APU start. To many memories to recall. Thanks for setting me straight on the Alaska R model and thanks for the info on the new Hydro fuel pumps. Learn something new every day.


OMG-Obama Must Go
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 52, posted (1 year 6 months 3 weeks 6 days 7 hours ago) and read 32767 times:

The Alaska incident was an "E" model. I was at Pease AFB when the NHANG "E" model caught fire. The airplane had no power on it, and maintenance was installing the new gaseous oxygen system (which replaced the LOX system). It was a second row of O2 gaseous bottles placed atop the O2 bottles already in place above the Boom Pod. When they charged the system by adding gaseous O2 to the new bottles, there was some grease still on one of the fittings. O2 and petroleum products do not mix well, and a fire started. It was an O2 feed fire until other materials caught fire and burned true the upper fuselage. The two NHANG Maintenance guys got out.

We worked very closely with the NHANG at Pease, and we talked a lot about the fire. The NHANG tanker was 57-1494, she sat at Pease, on the north ramp for years after the fire and was stripped of all useable parts.

http://airrefuelingarchive.wordpress...135-history-of-destroyed-aircraft/


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 53, posted (1 year 6 months 3 weeks 6 days 4 hours ago) and read 32767 times:

As I understand it, the third crew member still has not been located yet. The nose section of the tanker has not been found, also. This may indicate the two crew members that have been found were not in the forward section of the airplane at the time of the break-up. If this is true, they had a serious emergency as the Boom Operator and one Pilot were trying to handle the emergency, perhaps a fire, while the other pilot flew the airplane.

Is that what everyone else understands?


User currently offlineawacsooner From United States of America, joined Jan 2008, 1950 posts, RR: 1
Reply 54, posted (1 year 6 months 3 weeks 6 days 4 hours ago) and read 32767 times:

Any word if they've got the CVR?

User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 55, posted (1 year 6 months 3 weeks 6 days 3 hours ago) and read 32767 times:

Not that I have heard. Most KC-135 did not originally have CVRs, a few did, and none were built with an FDR. However they were equipped with both beginning a few years ago, IIRC. I don't know if the entire fleet has been equipped with them, yet.

BTW, the few tankers that did originally have a CVR, that was only for "tattle-tail" for receivers during refueling. SAC thought it some receivers were getting to talkative during refueling and the tanker crew did not have the ability to erase the recording.

Rumor has it some tanker crews used flashlights to indicate to (non-SAC) receivers their tanker was equipped with a CVR. SAC bomber crews could not be trusted. I will neither confirm nor deny that rumor.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 56, posted (1 year 6 months 3 weeks 6 days 2 hours ago) and read 32767 times:

I'm almost certain that all R-model 135s have a digital CVR and FDR installed. I know this because a CVR/FDR fail light prior to takeoff is a redball and a grounding writeup. If you all want I can get in touch with some pointy heads at work and find out exactly how the system works.

User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 57, posted (1 year 6 months 3 weeks 6 days 1 hour ago) and read 32767 times:

Quoting KC135TopBoom (Reply 53):
they had a serious emergency as the Boom Operator and one Pilot were trying to handle the emergency, perhaps a fire, while the other pilot flew the airplane.

Another possibility (assuming the report of 5 SOB) is that the nose section with the AC, CP, and BO has yet to be found and the cargo compartment with two pax (CC, etc.) has been located.


User currently offlinesolarflyer22 From US Minor Outlying Islands, joined Nov 2009, 1113 posts, RR: 0
Reply 58, posted (1 year 6 months 3 weeks 6 days 1 hour ago) and read 32767 times:

Quoting rc135x (Reply 23):
Two widely separated impact points may well mean something like in-flight fuselage failure form whatever cause at the wing junction causing two large sections of the airframe to come down far apart.

I hope this isnt due to age of the frame. Lord knows these things have been flying forever.


User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 59, posted (1 year 6 months 3 weeks 6 days ago) and read 32767 times:

Quoting solarflyer22 (Reply 58):
I hope this isnt due to age of the frame. Lord knows these things have been flying forever.

Yes.

Speculatively, if the AIB determines that a wing cracked off at the root due to spar failure from fatigue or corrosion, for example, or some other critical structural issue, then the impact of a fleet-wide grounding (like the F-22 or F-15C issues) of tankers would have a profound impact on the ability of the U.S. and its allies to project airpower. There is simply no substitute for tankers upon which nearly every U.S. aerial asset relies, to varying degree.

Consider the impact of losing, however temporary, 400+ KC-135s in terms of moving fighters to Japan/South Korea or the Gulf, or resupplying Israel in the event of an Israeli-Iran war or an expansion of the Israeli-Syrian conflict (as with the 1973 airlift). The implications would not be lost on potential adversaries.


User currently offlinecjg225 From United States of America, joined Feb 2013, 873 posts, RR: 0
Reply 60, posted (1 year 6 months 3 weeks 5 days 23 hours ago) and read 32767 times:

Quoting rc135x (Reply 59):
Consider the impact of losing, however temporary, 400+ KC-135s in terms of moving fighters to Japan/South Korea or the Gulf, or resupplying Israel in the event of an Israeli-Iran war or an expansion of the Israeli-Syrian conflict (as with the 1973 airlift). The implications would not be lost on potential adversaries.

That would be very bad, to say the least.

EDIT: I had forgotten that there was a "new" winner of the KC-X program, so disregard what I put here.

[Edited 2013-05-05 19:32:51]


Restoring Penn State's transportation heritage...
User currently offlinetitanmiller From United States of America, joined May 2006, 90 posts, RR: 0
Reply 61, posted (1 year 6 months 3 weeks 5 days 22 hours ago) and read 32767 times:

Quoting rc135x (Reply 50):
Our TOs state not to run the A/R pump with less than 2,000lbs in the body tanks

FYI, there is no aircrew restriction on pumping the body tanks down to 0.0 on the gage.

Quoting KC135Hydraulics (Reply 56):
Not that I have heard. Most KC-135 did not originally have CVRs, a few did, and none were built with an FDR. However they were equipped with both beginning a few years ago, IIRC. I don't know if the entire fleet has been equipped with them, yet.

All of the current fleet have both an FDR and CVR.


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 62, posted (1 year 6 months 3 weeks 5 days 11 hours ago) and read 32767 times:

Quoting rc135x (Reply 57):
Another possibility (assuming the report of 5 SOB) is that the nose section with the AC, CP, and BO has yet to be found and the cargo compartment with two pax (CC, etc.) has been located.

Good point. There are not any accurate news reports as to how many SOBs were aboard. I have seen reports of 3, 5, or 7 aboard.

I guess the one report of a parachute jump was not accurate, if it was, they would have found him by now.


User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 63, posted (1 year 6 months 3 weeks 5 days 10 hours ago) and read 32767 times:

According to the DOD three had been on board. Names in the article.

http://www.kake.com/home/mobile/Airm...ntified--206193491.html?mobile=yes

http://www.military.com/daily-news/2...led-in-kyrgyzstan-kc135-crash.html

Edited to add another link

[Edited 2013-05-06 08:12:07]


OMG-Obama Must Go
User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 64, posted (1 year 6 months 3 weeks 5 days 9 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Quoting KC135TopBoom (Reply 55):
Not that I have heard. Most KC-135 did not originally have CVRs, a few did, and none were built with an FDR. However they were equipped with both beginning a few years ago, IIRC. I don't know if the entire fleet has been equipped with them, yet.

Yes, CVR's are now on the birds, it was sometime between block 30 and block 40 upgrades. They don't always work, but the FDR's were mandated/required to always work.

135Mech

[Edited 2013-05-06 09:37:17]

User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 65, posted (1 year 6 months 3 weeks 5 days 5 hours ago) and read 32767 times:

I am happy the crew has been found. I am sad they did not survive.

Apparently, the accident investigation team is looking at the weather in the area at the time of the inflight break-up and subsequent crash, according to this story, which also says they found the crew.

http://rt.com/news/us-plane-crashes-kyrgyzstan-771/

"The Kyrgyz Interior Ministry launched a criminal investigation on Saturday into the deadly crash."

That will do nothing but impede the progress of the USAF Accident Investigation Board. A criminal investigation will want to control the wreckage and CVR/FDR as evidence. That will restrict the USAF's ability to send parts of wreckage to Tinker AFB, OK for analysis.

I have not heard of any theory as to why 2 of the crew was found in the center section of the wreckage.

Yes, I know, the top picture in the story is not a KC-135. It is an IDFAF KC-707 refueling an IDFAF F-16I. The caption identifies the tanker in the picture as a "KC-135 Stratotanker Boeing 707", then again it is also saying the receiver aircraft is an F-16C, but it is actually an F-16I.

Pictures lower in the story show various broken up pieces of the wing, vertical stabilizer, and tail sections of the KC-135R wreckage. I notice on these shown parts, there is no smoke soot or apparent fire damage.

I hope the crew has been flown to Germany for the autopsy and not done by the Kyrgyz Government.

RIP, my brothers and sister.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 66, posted (1 year 6 months 3 weeks 5 days 1 hour ago) and read 32767 times:

Quoting titanmiller (Reply 61):
FYI, there is no aircrew restriction on pumping the body tanks down to 0.0 on the gage.

There isn't, that I am aware, but I have had some debriefs about the low pressure lights coming on for the A/R pumps operating in tanks with very low fuel (below 2k), or with a small amount of fuel in tank but in a bank. Once the pump inlets are partially uncovered the pumps will start sucking air. That's 2,000lbs of fuel spread across 4 bladders, so in reality it's a very low fuel level in the actual bladder were the pumps are instaled.

Anyway, I am happy that all of the crew members were found. That will help their families move forward during this difficult time.


User currently offlinerfields5421 From United States of America, joined Jul 2007, 7607 posts, RR: 32
Reply 67, posted (1 year 6 months 3 weeks 5 days 1 hour ago) and read 32767 times:

Quoting KC135TopBoom (Reply 62):
There are not any accurate news reports as to how many SOBs were aboard. I have seen reports of 3, 5, or 7 aboard.

A DOD press release I received today listed three crew members as killed. Two 27 year old Captains as the pilots and a 30 year old Tech Sargent. They were apparently from the 93rd Air Refueling Squadron out of Fairchild.

http://www.amc.af.mil/news/story.asp?id=123347167


User currently offlinecargotanker From United States of America, joined Oct 2009, 164 posts, RR: 1
Reply 68, posted (1 year 6 months 3 weeks 5 days ago) and read 32767 times:

Quoting KC135TopBoom (Reply 65):
I have not heard of any theory as to why 2 of the crew was found in the center section of the wreckage

Coupled with what I have read from various sources that the plane was noticed by people on the ground before it separated in mid-air (some said it was on fire) and that it was apparently a lot lower than it should have been at that part of its mission (100nm from Manas, should have been over 20K feet but accounts from eyewitnesses seem to suggest less than 10) lead me to speculate that there was an onboard problem before the catastrophic explosion/separation. Maybe the co-pilot was in the back with the boom fighting a fire?

Pure speculation and guesses based on inconsistent news reports.

This accident is an odd one. Not too many accidents have involved mid-air explosion/separations.


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 69, posted (1 year 6 months 3 weeks 4 days 3 hours ago) and read 32767 times:

Quoting cargotanker (Reply 68):
Coupled with what I have read from various sources that the plane was noticed by people on the ground before it separated in mid-air (some said it was on fire) and that it was apparently a lot lower than it should have been at that part of its mission (100nm from Manas, should have been over 20K feet but accounts from eyewitnesses seem to suggest less than 10) lead me to speculate that there was an onboard problem before the catastrophic explosion/separation. Maybe the co-pilot was in the back with the boom fighting a fire?

Pure speculation and guesses based on inconsistent news reports.

That is what I speculated, too.

Quoting KC135TopBoom (Reply 53):
As I understand it, the third crew member still has not been located yet. The nose section of the tanker has not been found, also. This may indicate the two crew members that have been found were not in the forward section of the airplane at the time of the break-up. If this is true, they had a serious emergency as the Boom Operator and one Pilot were trying to handle the emergency, perhaps a fire, while the other pilot flew the airplane.

Is that what everyone else understands?

cargotanker, the speculation the tanker may have been at, or around 10,000' makes sense, too. As you know the crew does not have to carry supplemental O2. But, then again, if they had on the firefighter's mask, they would need to be connected to a portable O2 supply. It would be interesting if any of the crew was wearing any O2 equipment. As I recall, BOLD PRINT for the smoke and fire checklist had 100% OXYGEN-P, CP, N, BO as the first checklist item. I assume it is still the same.


User currently offlinecargotanker From United States of America, joined Oct 2009, 164 posts, RR: 1
Reply 70, posted (1 year 6 months 3 weeks 4 days 2 hours ago) and read 32767 times:

Quoting KC135TopBoom (Reply 69):
cargotanker, the speculation the tanker may have been at, or around 10,000' makes sense, too. As you know the crew does not have to carry supplemental O2. But, then again, if they had on the firefighter's mask, they would need to be connected to a portable O2 supply. It would be interesting if any of the crew was wearing any O2 equipment. As I recall, BOLD PRINT for the smoke and fire checklist had 100% OXYGEN-P, CP, N, BO as the first checklist item. I assume it is still the same.

So, what kind of explosion on a tanker, or any aircraft, would separate into distinct areas: a wing, the vertical stab, the cockpit/forward section, the boom, and then the rest of the aircraft? There was enough gas in those wings and body tanks to blow everything apart, but it doesn't seem like it happened that way. The 'chunks' would have been smaller.

I also read recently thunderstorms were in the area and the aircraft might have flown through them. Structural damage leading to a later breakup? This is puzzling.


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 71, posted (1 year 6 months 3 weeks 4 days 1 hour ago) and read 32767 times:

Weather could be a factor in the accident.

The only thing I can think of to blow up a KC-135 into 3 sections, as reported by witnesses would be a problem with the center wing fuel tank. Since this was a combat mission, I assume they had at least 160,000 lbs. of fuel aboard. This would mean the CWT was full at T/O, about 48,000 lbs. of fuel, IIRC. If the normal fuel burn sequence we used in SAC are still in use, then the crew would start burning from the CWT soon after T/O and clean up of the flaps and gear. IIRC the fuel override pumps in the CWT are electrically powered and produced higher pressures than the main wing tank boost pumps. Assuming this somehow started a fire that entered the cargo compartment, an explosion may happen soon after the fire gets into the cargo compartment and burns through the common fuel vent manifold for the two body and upper deck tank.

This is only a guess. I have no knowledge if this has ever happened. But the fuel vent manifold is a much, much thinner aluminum manifold than the fuel manifolds are, because they do not need to hold pressure.


User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 72, posted (1 year 6 months 3 weeks 4 days 1 hour ago) and read 32767 times:

Quoting KC135TopBoom (Reply 53):
This may indicate the two crew members that have been found were not in the forward section of the airplane at the time of the break-up. If this is true, they had a serious emergency as the Boom Operator and one Pilot were trying to handle the emergency, perhaps a fire, while the other pilot flew the airplane.

The in-flight fire theory is certainly plausible. Given the short flight timeline, the fire would have erupted sometime after takeoff during the climb out. If it was bad enough for the BO and (especially) the CP to go to the cargo compartment to combat the blaze then the AC would have been thinking about the WARNING in the Dash One that says in the event of an in-flight uncontrolled fire land as soon as *possible*. I noticed that amidst all the mountainous terrain there was enough open area to allow an opportunity to land the airplane. This "crisis" situation might explain the apparent absence of any radio transmission from the airplane.

Quoting KC135TopBoom (Reply 53):
As I understand it, the third crew member still has not been located yet.

Doesn't the BO check off during the climb to go aft to do a boom check? If so then the crewmembers would have been where they would normally be during this phase of flight, suggesting the problem occurred without warning and the crew was attempting to get below 10K for cabin pressurization/oxygen requirements. One explanation for this scenario might be massive structural fatigue failure resulting in rapid decompression, ultimately causing in-flight break up.

I have not seen any further impact site photos which could clarify what might have happened.

I hope further details will be available. Aside from the importance of preventing similar incidents in the future, it is equally important to the families of the three fliers who need to know what happened to their loved ones.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 73, posted (1 year 6 months 3 weeks 4 days 1 hour ago) and read 32767 times:

Quoting KC135TopBoom (Reply 71):
If the normal fuel burn sequence we used in SAC are still in use, then the crew would start burning from the CWT soon after T/O and clean up of the flaps and gear. IIRC the fuel override pumps in the CWT are electrically powered and produced higher pressures than the main wing tank boost pumps.

You are absolutely correct. The two center wing fuel pumps, also known as override pumps, produce more pressure than the wing tank pumps and can "override" them.


User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 74, posted (1 year 6 months 3 weeks 3 days 12 hours ago) and read 32767 times:

Does anyone know if the crew was within radio range of anyone or still under any kind of ATC control at this point. Nothing has been mentioned in any of the articles by the DOD if there was any distress calls. Correct me if I am wrong but at 100 miles the should still be in VHF range of the tower.


OMG-Obama Must Go
User currently offlinebikerthai From United States of America, joined Apr 2010, 2170 posts, RR: 4
Reply 75, posted (1 year 6 months 3 weeks 3 days 11 hours ago) and read 32767 times:

Quoting cargotanker (Reply 70):
the vertical stab, the cockpit/forward section, the boom, and then the rest of the aircraft?

You can probably take the vertical stab and the boom out of the original break-up equation for now.

Reason being the vertical, and sometimes the horizontal stabilizer are large surface that can separate on their own if the rear section of the airplane breaks off and start to tumble.

Same would probably be true for the boom from a mass dynamic stand point.

bt



Intelligent seeks knowledge. Enlightened seeks wisdom.
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 76, posted (1 year 6 months 3 weeks 3 days 9 hours ago) and read 32767 times:

Quoting rc135x (Reply 72):
Quoting KC135TopBoom (Reply 53):As I understand it, the third crew member still has not been located yet.
Doesn't the BO check off during the climb to go aft to do a boom check? If so then the crewmembers would have been where they would normally be during this phase of flight, suggesting the problem occurred without warning and the crew was attempting to get below 10K for cabin pressurization/oxygen requirements. One explanation for this scenario might be massive structural fatigue failure resulting in rapid decompression, ultimately causing in-flight break up.

Yes, there are after take-off checks done in the Boom Pod, so yes, the BO would have checked off interphone.

Quoting windy95 (Reply 74):
Does anyone know if the crew was within radio range of anyone or still under any kind of ATC control at this point. Nothing has been mentioned in any of the articles by the DOD if there was any distress calls. Correct me if I am wrong but at 100 miles the should still be in VHF range of the tower.

They should have been well within VHF and UHF range. Both the VHF and UHF radios are "line-of-site" radios, meaning there must be no obstructions (such as mountains) between the airplane and the ground stations. At 10,000' this should be no problem.

I looked at the general area of the crash site(s) on google earth, and it looks like the only airports in the area are small grass strips. A KC-135 could land there but will forever be stuck there. Its weight would sink into the ground and the tanker will be damaged upon landing. This would only be attempted as a last resort, bail-out would be preferred to landing a big airplane like a KC-135 on a short grass landing strip.


User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 77, posted (1 year 6 months 3 weeks 3 days 9 hours ago) and read 32767 times:

Quoting KC135TopBoom (Reply 76):
This would only be attempted as a last resort, bail-out would be preferred to landing a big airplane like a KC-135 on a short grass landing strip.

Good point. I was thinking that if time precluded a bail out then just get it on the ground, not necessarily a landing strip but any flat open area. Walking or crawling away from a burning hulk is worth a try considering the alternative.

FLAPS - 50
GEAR - DOWN (UNLESS OVER WATER)
THROTTLES - CUT OFF AFTER TOUCHDOWN

But this is all arm chair quarterbacking. Sigh.


User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 78, posted (1 year 6 months 3 weeks 3 days 9 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Quoting rc135x (Reply 77):
Quoting KC135TopBoom (Reply 76):
This would only be attempted as a last resort, bail-out would be preferred to landing a big airplane like a KC-135 on a short grass landing strip.

Good point. I was thinking that if time precluded a bail out then just get it on the ground, not necessarily a landing strip but any flat open area. Walking or crawling away from a burning hulk is worth a try considering the alternative.

FLAPS - 50
GEAR - DOWN (UNLESS OVER WATER)
THROTTLES - CUT OFF AFTER TOUCHDOWN

But this is all arm chair quarterbacking. Sigh.

I have a question, yes the book calls for gear down, BUT... it you were to land on grass in that area, wouldn't a gear up belly landing be better for the frame, especially for not tearing off the gear?

Yes, this is hypothetical, but the mechanic/troubleshooter in me is curious.

135Mech


User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 79, posted (1 year 6 months 3 weeks 3 days 8 hours ago) and read 32767 times:

Quoting 135mech (Reply 78):
I have a question, yes the book calls for gear down, BUT... it you were to land on grass in that area, wouldn't a gear up belly landing be better for the frame, especially for not tearing off the gear?

The gear will help cushion the impact and begin to slow the airplane. At this point the airplane is a write off anyway, so saving the crew is the priority.


User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 80, posted (1 year 6 months 3 weeks 3 days 7 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Quoting rc135x (Reply 79):
Quoting 135mech (Reply 78):
I have a question, yes the book calls for gear down, BUT... it you were to land on grass in that area, wouldn't a gear up belly landing be better for the frame, especially for not tearing off the gear?

The gear will help cushion the impact and begin to slow the airplane. At this point the airplane is a write off anyway, so saving the crew is the priority.



Good to know, thanks! Agreed too, if the incident wasn't what these 3 went through, then it would be take all aspects into account and end result help minimize total impact. That one (8886) at Manas a few years back with the wing collision/fire... did you see the pictures later, they just had to cut the whole thing up and truck it out to get it "out" of there.

I'd never want to know what they went through in the final moments... just dreadful!

135Mech


User currently offlinebikerthai From United States of America, joined Apr 2010, 2170 posts, RR: 4
Reply 81, posted (1 year 6 months 3 weeks 3 days 6 hours ago) and read 32767 times:

Quoting rc135x (Reply 79):
The gear will help cushion the impact and begin to slow the airplane.

Yeah but . . .

Sure you're not worried about losing the gears, but in doing so, you are worried about the gear ripping off more important structure on it's way off.

The engines have shear pins that will help give it a clean break. Don't know about the gears.

what is the procedure for a water landing? Gears up or down?

bt



Intelligent seeks knowledge. Enlightened seeks wisdom.
User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 82, posted (1 year 6 months 3 weeks 3 days 6 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Quoting bikerthai (Reply 81):
Quoting rc135x (Reply 79):
The gear will help cushion the impact and begin to slow the airplane.

Yeah but . . .

Sure you're not worried about losing the gears, but in doing so, you are worried about the gear ripping off more important structure on it's way off.

The engines have shear pins that will help give it a clean break. Don't know about the gears.

what is the procedure for a water landing? Gears up or down?

bt

Hello BT,

The gear also have shear pins/points on them, so if it got that rough they would "in design" break off directly behind where they currently sit and [hopefully] not do too much damage to anything else.

135Mech


User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 83, posted (1 year 6 months 3 weeks 3 days 4 hours ago) and read 32767 times:

Quoting bikerthai (Reply 81):
Sure you're not worried about losing the gears, but in doing so, you are worried about the gear ripping off more important structure on it's way off.

Remember the assumption here is that the airplane is already a write-off prior to crash landing. Any damage caused by the gear is irrelevant.

Quoting bikerthai (Reply 81):
what is the procedure for a water landing? Gears up or down?

Gear up for ditching.


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 84, posted (1 year 6 months 3 weeks 3 days 3 hours ago) and read 32767 times:

Quoting bikerthai (Reply 81):
The engines have shear pins that will help give it a clean break.

Normally the engines will not break off the airplane once the gear has sheared away, until the airplane fuselage changes heading but still (generally continues to slide in its original direction). The airplane should slide for a distance on the engine nacelles.

The engine mounting is designed to shear off the engines, and struts during a water ditching to reduce the water from dragging the remaining airplane underwater, where it may not resurface. If the fuel has been dumped before the airplane hits the water, the remaining airplane should float, at least for a few minutes.

Remember, the KC-135 was designed at a time when piston airplanes ditched at sea about 3-4 times per year. There are accounts of KC-97s that ditched and floated for so long they became a hazard to navigation and had to be sunk by US Navy or Coast Guard gun fire.

As RC135x pointed out with the BOLD FACE checklist items for crash landing or ditching, the Pilot is to cut off the engines at touchdown. This reduces, but does not eliminate the possibility of fire.

Just check out the YouTube video of the LOT B-767-300ER landing without landing gear last year, or "Capt. Sully's" US Airways A-320 ditching in the Hudson River a few years ago.


User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 85, posted (1 year 6 months 3 weeks 2 days 13 hours ago) and read 32767 times:

A little spat is now going on over the accident investigation. The FDR/CVR's might be sent to Russia to be read.

http://www.eurasianet.org/node/66935



OMG-Obama Must Go
User currently offlinebikerthai From United States of America, joined Apr 2010, 2170 posts, RR: 4
Reply 86, posted (1 year 6 months 3 weeks 2 days 12 hours ago) and read 32767 times:

Quoting windy95 (Reply 85):

Oops, I would assume that there are some sensitive com gear on the aircraft. If the airplane broke up fast, I would assume that they do not have time to destroy those equipment. Wonder if any would survive the crash?

Quoting rc135x (Reply 83):
Any damage caused by the gear is irrelevant.

From a write off standpoint yes. From a structural standpoint you don't want any other critical structure to fail (like the floor beams or wing box) prior to the airplane stopping. You want as much of those structure to stay in tact to absorb as much of the crash as possible.

But as you said the gears do have shear pins, so the design has taken that into account.

bt



Intelligent seeks knowledge. Enlightened seeks wisdom.
User currently offlinecjg225 From United States of America, joined Feb 2013, 873 posts, RR: 0
Reply 87, posted (1 year 6 months 3 weeks 2 days 12 hours ago) and read 32767 times:

Quoting windy95 (Reply 85):
A little spat is now going on over the accident investigation. The FDR/CVR's might be sent to Russia to be read.

http://www.eurasianet.org/node/66935

That sounds like something a little child would do...



Restoring Penn State's transportation heritage...
User currently offlinecargotanker From United States of America, joined Oct 2009, 164 posts, RR: 1
Reply 88, posted (1 year 6 months 3 weeks 2 days 10 hours ago) and read 32767 times:

Weather might be a factor. According to the article below the crew requested to deviate from thunderstorms. Also of note is that the crew had radio contact with Kyrgyz controllers close to the time of the crash.

http://www.kxly.com/news/spokane-new...14/20071914/-/pdp945z/-/index.html


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 89, posted (1 year 6 months 3 weeks 2 days 9 hours ago) and read 32767 times:

Here are pictures of some of the wreckage, mostly of the center wing section, which ended up in a drainage ditch. There are also pictures of 3 of the 4 engines, 2 of which show smoke soot of fire damage to the cowlings. Also, in some pictures are the main landing gear, in the stowed position as they would be inside the center wing section.

http://news.yahoo.com/us-military-pl...-crashes-kyrgyzstan-150442087.html

I none of these pictures do I see any uniformed US Military personnel, but there are a few people in blue jeans.

There are some shots of the right wing section near the wing tip. It still had the outboard flap, inboard and outboard ailerons attached. Parts of the tanker are spread over a 2 square mile area, and the tanker came down near an electrical power station. There does not seem to be any evidence or remains of any cargo that may have been aboard, so I think we can rule out a cargo fire. I have not found and pictures of the tail and nose sections yet. Nor do I know the location relationship these pictured part have to one another. It seems the 3 shown engines partially buried themselves into the field, and I noticed the tail pipes were all crushed.

Maybe it is time the US took control of the wreckage, black boxes, and the crew and placed the location under guard by US Marines? The KC-135 would have had at least one classified electronic part aboard, an possibly more than one. There would also have been classified documents aboard.

This link say the tanker carried "70 tons of fuel" which would be a 140,000 lb standard fuel load, as opposed to the 160,000 lb fuel load I guessed at earlier.

http://www.nydailynews.com/news/worl...crash-kyrgyzstan-article-1.1335068

Inverted KC-135 tail and horizontal stabilizer with elevators attached and Boom Hoist Motor in the forground.

http://news.yahoo.com/photos/view-sh...;_ylt=AkdtB_uoE_ULcVD5uLbSSM3RtDMD


User currently offlinezeke From Hong Kong, joined Dec 2006, 9210 posts, RR: 76
Reply 90, posted (1 year 6 months 3 weeks 2 days 9 hours ago) and read 32767 times:

Quoting windy95 (Reply 85):

A little spat is now going on over the accident investigation. The FDR/CVR's might be sent to Russia to be read.

I see no reason for the "spat", to me they are treating the accident the same as any other accident they would look in Kyrgyzstan.

The article states "The formal agreements between the U.S. and Kyrgyzstan governments don't expressly address the legal jurisdiction in this sort of situation", this is different to Japan where the Japan-U.S. Security Arrangements have legally agreed procedures prepared in advance, and training for military accidents and investigation.

To me it looks like Kyrgyzstan is following the standard ICAO Annex 13 accident investigation process, which is their legal obligation under ICAO. http://www.rnf.is/media/eydublod/Annex_13.pdf

"Flight recorders — Accidents and incidents
5.7 Effective use shall be made of flight recorders in the investigation of an accident or an incident. The State conducting
the investigation shall arrange for the read-out of the flight recorders without delay.
5.8 Recommendation.—In the event that the State conducting the investigation of an accident or an incident does not
have adequate facilities to read out the flight recorders, it should use the facilities made available to it by other States, giving
consideration to the following:
a) the capabilities of the read-out facility;
b) the timeliness of the read-out; and
c) the location of the read-out facility.
Note.— The requirements for the recording of radar data and ATS communications are contained in Annex 11, Chapter 6."

I am not sure what the USAF is worried about, it is just a CVR/FDR.



We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
User currently offlineSSTeve From United States of America, joined Dec 2011, 726 posts, RR: 2
Reply 91, posted (1 year 6 months 3 weeks 2 days 7 hours ago) and read 32767 times:

Quoting zeke (Reply 90):
I am not sure what the USAF is worried about, it is just a CVR/FDR.

  They're worried about getting the data from both in an expedient manner?


User currently offlineeksath From United States of America, joined Aug 2004, 1317 posts, RR: 25
Reply 92, posted (1 year 6 months 3 weeks 2 days 6 hours ago) and read 32767 times:
AIRLINERS.NET CREW
ARTICLE EDITOR

Folks,

Normally, I am hesitant about commercial plugging however I think this is a good cause and worthy endeavor. It was brought to my attention first hand by a friend in the FAA hence I can attest to the validity of it.

If you have a moment, please read and share this post in support of the 3 USAF members killed in the recent KC135 crash overseas, (callsign SHELL77). One of the victims is the daughter of a a retired controller from LA Center. He lost his daughter Tori, a USAF Captain in this crash.

http://www.stripes.com/news/air-forc...n-kyrgyzstan-kc-135-crash-1.219776

Please consider supporting the families by purchasing a shirt honoring the fallen warriors of Shell 77shirt.

All of the proceeds of shirt will go to the families of Voss, Pinckney and Mackey.

http://campaign.customink.com/shell77


I have ordered mine.



World Wide Aerospace Photography
User currently offlinerfields5421 From United States of America, joined Jul 2007, 7607 posts, RR: 32
Reply 93, posted (1 year 6 months 3 weeks 2 days 4 hours ago) and read 32767 times:

Quoting zeke (Reply 90):
To me it looks like Kyrgyzstan is following the standard ICAO Annex 13 accident investigation process, which is their legal obligation under ICAO

Maybe I'm being simplistic by ICAO is the International Civil Aeronautical Organization.

This was a military aircraft operated under military control. It doesn't come under ICAO rules at all.

In most nations - military aircraft crash investigations are not conducted by civil authorities. They might be used for technical analysis. But not as the primary investigation agency.


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 94, posted (1 year 6 months 3 weeks 2 days 4 hours ago) and read 32767 times:

Quoting zeke (Reply 90):
To me it looks like Kyrgyzstan is following the standard ICAO Annex 13 accident investigation process, which is their legal obligation under ICAO.
Quoting rfields5421 (Reply 93):
Maybe I'm being simplistic by ICAO is the International Civil Aeronautical Organization.

This was a military aircraft operated under military control. It doesn't come under ICAO rules at all.

In most nations - military aircraft crash investigations are not conducted by civil authorities.

Correct. Shell-77 was a military aircraft on a combat mission when the accident happened. The entire wreckage site, responsibility for the accident investigation, taking care of the crew, site clean up after the investigation, and any compensation due are all the responsibility of the US Air Force.

This accident does not fall under the rules of the ICAO. It would fall under the status of forces agreement between the United States and Kyrgyzstan.


User currently offlineLTC8K6 From United States of America, joined Jun 2009, 1211 posts, RR: 0
Reply 95, posted (1 year 6 months 3 weeks 2 days ago) and read 32767 times:

http://media.zenfs.com/en_us/News/Re...DP_3_KYRGYZSTAN-US-PLANE-CRASH.JPG

High res pic of tail and boom motor mentioned earlier.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 96, posted (1 year 6 months 3 weeks 1 day 21 hours ago) and read 32767 times:

Quoting LTC8K6 (Reply 95):
http://media.zenfs.com/en_us/News/Re...DP_3_KYRGYZSTAN-US-PLANE-CRASH.JPG

High res pic of tail and boom motor mentioned earlier.

Thought you guys might want a clarification. That is most definitely not the boom hoist unit. The hoist unit is painted black and would have two hydraulic motors on either side of the drum. What you're actually looking at is the stab trim actuator/unit/assembly/setup. If you look at the top you'll notice a large jack screw, that's the jack screw that horizontal stabilizer moves up or down on. The cable drum underneath is what is used to manually move the stabilizer up and down from the wheel on the pilot's side of the pedestal, and it also moves the wheel up there when the stab is being trimmed electrically. The only reason I know all this is because I do quite a bit of maintenance on the boom hoist unit in the tail compartment, and the stab trim actuator setup is directly underneath it, and the jackscrew is in the way and completely covered in grease so it leaves a distinctive greasy spiraly pattern on my uniform.

[Edited 2013-05-09 21:43:55]

User currently offlineLTC8K6 From United States of America, joined Jun 2009, 1211 posts, RR: 0
Reply 97, posted (1 year 6 months 3 weeks 1 day 20 hours ago) and read 32767 times:

Quoting KC135Hydraulics (Reply 96):
That is most definitely not the boom hoist unit.

Thanks, I didn't know what it was other than "winch-looking part"...


User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 98, posted (1 year 6 months 3 weeks 1 day 10 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Quoting eksath (Reply 92):
Please consider supporting the families by purchasing a shirt honoring the fallen warriors of Shell 77shirt.

All of the proceeds of shirt will go to the families of Voss, Pinckney and Mackey.

http://campaign.customink.com/shell77


I have ordered mine.

Thank you for the link! Ordered mine too! May the families find peace in time!

135Mech


User currently offlinezeke From Hong Kong, joined Dec 2006, 9210 posts, RR: 76
Reply 99, posted (1 year 6 months 3 weeks 1 hour ago) and read 32767 times:

Quoting rfields5421 (Reply 93):
In most nations - military aircraft crash investigations are not conducted by civil authorities. They might be used for technical analysis. But not as the primary investigation agency.

While the NTSB have a specific mandate not to investigate military accidents, that is not universal. Many countries have a single agency for such investigations. In Kyrgyzstan I understand that the investigation role is shared between the prosecutor and the russian aviation committee.

I understand this was a state aircraft, however unlike a lot of countries the USAF operate out of, it has been reported they do not have the legal agreement to overturn the crash site to the USAF. The base is a political hot potato, is I do not see them going in trying to take over the crash site.



We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 100, posted (1 year 6 months 2 weeks 6 days 14 hours ago) and read 32767 times:

You could be right, the US will not take over the crash site. Even if there is no agreement on who investigates a US aircraft crash in Kyrgyzstan, there would be one on who controls US classified documents, equipment, and information.

User currently offlinezeke From Hong Kong, joined Dec 2006, 9210 posts, RR: 76
Reply 101, posted (1 year 6 months 2 weeks 6 days 14 hours ago) and read 32767 times:

Quoting KC135TopBoom (Reply 100):
Even if there is no agreement on who investigates a US aircraft crash in Kyrgyzstan, there would be one on who controls US classified documents, equipment, and information.

No doubt, I have not seen anything to suggest they are removing classified material, if any actually survived the fire. I would assume that they would have enough information (photos/survey) by now and collected the necessary metallurgical samples to hand all the debris over to owner. The cleanup of the site will probably take some specialist work due do the amount of hazardous material involved.

I had seen reports they had recovered 2 of the crew, has it been confirmed they have also recovered all three crew lost ? I know they have released the names and ranks of the crew involved, I had not seen news of the recovery. Just an extra reason in my view to be sensitive in the cleanup.

Does anyone know where the HF antenna coupler is in stalled on these modified R models ?



We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 102, posted (1 year 6 months 2 weeks 6 days 4 hours ago) and read 32767 times:

The coupler is installed inside the fuselage, cargo compartment, right hand side just above the little galley. There are of course two HF antennas.. one is the large probe you saw detached from the vertical stabilizer lying on the ground and the other is a wire that stretches from about midpoint on the vertical stabilizer to just about where the coupler is on the fuselage. For reference, the coupler is installed just aft of the emergency depressurization valve if you're familiar with that.

User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 103, posted (1 year 6 months 2 weeks 6 days 3 hours ago) and read 32767 times:

Quoting zeke (Reply 101):
I had seen reports they had recovered 2 of the crew, has it been confirmed they have also recovered all three crew lost ? I know they have released the names and ranks of the crew involved, I had not seen news of the recovery.

The USAF would not have released the 3 names of the crew unless they confirmed any or all of the crew did not survive. If they thought anyone may have survived, they would continued the CSAR missions beyond the first few days. Those missions ended after about 3 days after the crash, meaning they had found the missing crewmember.


User currently offlinemoriarty From Sweden, joined Jan 2006, 190 posts, RR: 0
Reply 104, posted (1 year 6 months 2 weeks 5 days 15 hours ago) and read 32767 times:

Quoting zeke (Reply 26):
Initial reports were the aircraft broke up into 3 pieces in flight with an explosion. The picture in reply 22 would indicate 2 impact locations, and the one you saw on fox the third possibly.

I'd say there's three impact locations on that picture. One to the left, two on the right side, the far most a fire ball.

Nevertheless, may the crew RIP and the cause of crash found and remedied.



Proud to part of www.novelair.com.
User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 105, posted (1 year 6 months 2 weeks 4 days 7 hours ago) and read 32767 times:
Support Airliners.net - become a First Class Member!

Quoting zeke (Reply 101):
Does anyone know where the HF antenna coupler is in stalled on these modified R models ?
Quoting KC135Hydraulics (Reply 102):
The coupler is installed inside the fuselage, cargo compartment, right hand side just above the little galley. There are of course two HF antennas.. one is the large probe you saw detached from the vertical stabilizer lying on the ground and the other is a wire that stretches from about midpoint on the vertical stabilizer to just about where the coupler is on the fuselage. For reference, the coupler is installed just aft of the emergency depressurization valve if you're familiar with that.



Howdy! There are now 2 HF antennas/couplers on each KC-135R/T's, the original and still used is in the top of the tail and still uses the distinct 707/135 probe at the top of the tail and the second was added during Block 35 or 40 upgrade of the Glass Cockpit/Pacer Crag and that is in the cargo deck just aft of the cockpit, which utilizes the long-wire antenna from the fwd body attached to the lower vertical stab. The second one was added for HF reliability for the over-water flights etc.

135Mech


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 106, posted (1 year 6 months 2 weeks 3 days 21 hours ago) and read 32647 times:

I must be confused. I thought the coupler was used to tie in multiple HF radios so they can work together. It was my understanding that the wire and probe on the tail were just antennas, and the actual coupler was the large black box near the galley. Of course I am not COMM/NAV!

User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 107, posted (1 year 6 months 2 weeks 3 days 9 hours ago) and read 32531 times:
Support Airliners.net - become a First Class Member!

Quoting KC135Hydraulics (Reply 106):
I must be confused. I thought the coupler was used to tie in multiple HF radios so they can work together. It was my understanding that the wire and probe on the tail were just antennas, and the actual coupler was the large black box near the galley. Of course I am not COMM/NAV!

You are correct on the "coupling" aspect of it, but, there's another (the original) large black box in the top of the tail attached to that probe. They added the second coupler/black box in the upgrades; because if the one and only coupler in the top of the tail went out, that was it... grounded until R2'ing... adding the second one, in the climate controlled cabin (above the galley) more than doubled their HF reliability, and that added "HF-2".

135Mech

[Edited 2013-05-15 09:04:19]

User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 108, posted (1 year 5 months 3 weeks 6 days 4 hours ago) and read 31138 times:
Support Airliners.net - become a First Class Member!

So, has anyone seen any updates on this yet?

135Mech


User currently offlineeksath From United States of America, joined Aug 2004, 1317 posts, RR: 25
Reply 109, posted (1 year 5 months 3 weeks 4 days 6 hours ago) and read 30634 times:
AIRLINERS.NET CREW
ARTICLE EDITOR

Quoting 135mech (Reply 98):
Thank you for the link! Ordered mine too! May the families find peace in time!

135Mech

No update on my radar.

But, the memorial T-shirt arrived last week. Hope yours did too.


Eksath



World Wide Aerospace Photography
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 110, posted (1 year 5 months 3 weeks 4 days 6 hours ago) and read 30649 times:

I doubt we will hear anything until the official accident report is released. That could take up to a year, or more.

The rumors I have heard indicate a severe weather related event, such as severe turbulence or wind shear. There was severe weather in the area of the accident, including thunderstorms, at that time. But none of these rumors come from any official source.


User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 111, posted (1 year 5 months 3 weeks 4 days ago) and read 30601 times:
Support Airliners.net - become a First Class Member!

Quoting eksath (Reply 109):
No update on my radar.

But, the memorial T-shirt arrived last week. Hope yours did too.


Eksath

Thanks, mine arrived 2 days ago... was happy and sad at the same time!

Quoting KC135TopBoom (Reply 110):
I doubt we will hear anything until the official accident report is released. That could take up to a year, or more.

The rumors I have heard indicate a severe weather related event, such as severe turbulence or wind shear. There was severe weather in the area of the accident, including thunderstorms, at that time. But none of these rumors come from any official source.

Thanks, and yeah, just don't like that these things (esp military) take soooo long!

Regards,
135Mech


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 112, posted (1 year 3 months 3 weeks 1 day 22 hours ago) and read 26961 times:

Have there been any updates on the possible causes of the crash? I think I read somewhere in another thread the possibility of overuse of the rudder in flight which caused structural failure being the leading cause, but I have no source for that.

It would be quite interesting if this is the cause given the presense of the rudder pressure reducing valve which reduces hydraulic pressure to the rudder PCU to 2250PSI +/- 100 when the flaps are up and power rudder is on. That would either mean to me that they were dramatically abusing the rudder at its lower pressure limit or they were flying with flaps extended, at least to 20 degrees, which would give them full pressure to the PCU. Again, I'm totally guessing here given the overall lack of information available to me.


User currently offlinecargotanker From United States of America, joined Oct 2009, 164 posts, RR: 1
Reply 113, posted (1 year 3 months 3 weeks 1 day 6 hours ago) and read 26886 times:

Quoting KC135Hydraulics (Reply 112):
Have there been any updates on the possible causes of the crash?

The AF Safety report has been released and you might be able to view it at your wing safety office if you have a good reason. I'm not sure when the public accident report will be released.

I've looked at the report, definitely a unique accident but that's all I can say for now.


User currently offlinevenus6971 From United States of America, joined Dec 2004, 1443 posts, RR: 0
Reply 114, posted (1 year 3 months 3 weeks 6 hours ago) and read 26505 times:

Quoting cargotanker (Reply 113):
he AF Safety report has been released and you might be able to view it at your wing safety office if you have a good reason. I'm not sure when the public accident report will be released.

I've looked at the report, definitely a unique accident but that's all I can say for now.

Anything us mechanics need to look at more thoroughly?



I would help you but it is not in the contract
User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 115, posted (1 year 3 months 2 weeks 6 days 10 hours ago) and read 26283 times:

Quoting venus6971 (Reply 114):
Anything us mechanics need to look at more thoroughly?

From what I understand, no. It is for the flight crew.



OMG-Obama Must Go
User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 116, posted (1 year 3 months 2 weeks 6 days 10 hours ago) and read 26399 times:

Quoting KC135Hydraulics (Reply 112):
I think I read somewhere in another thread the possibility of overuse of the rudder in flight which caused structural failure being the leading cause

Resetting the Rudder PCU CB in flight while having the crew put pressure on the rudder pedal keeping the aircraft straight manually is not a good idea.



OMG-Obama Must Go
User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 117, posted (1 year 3 months 2 weeks 6 days 10 hours ago) and read 26440 times:

For those who have not heard the FCIF was out last month which gave an idea as to what happened. Then the SIB was released about three weaks ago and then quickly pulled for some reason. It has now been re-released yesterday with the AIB to follow soon.


OMG-Obama Must Go
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 118, posted (1 year 3 months 2 weeks 6 days 2 hours ago) and read 26218 times:

I agree with cargotanker, this was a very unique kind of accident.

[Edited 2013-08-10 16:22:02]

User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 119, posted (1 year 3 months 1 week 3 days 10 hours ago) and read 24576 times:
Support Airliners.net - become a First Class Member!

Howdy,

Haven't been on in a bit, and with our B-1 going down yesterday, thought I'd see what's new on here. Does anyone have the links to these reports?

Thanks!

135Mech


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 120, posted (1 year 2 months 5 days 2 hours ago) and read 21964 times:

Well I just got the spiel! I'll summarize this very briefly as the classification of the briefing I received was vague. There was an encounter with a Dutch roll condition and actions taken (or not taken) to recover led to the vertical fin being overloaded and it snapped off in flight. That's all I really feel comfortable saying at this point.

User currently offlinecjg225 From United States of America, joined Feb 2013, 873 posts, RR: 0
Reply 121, posted (1 year 2 months 4 days 13 hours ago) and read 21614 times:

Quoting KC135Hydraulics (Reply 120):
Well I just got the spiel! I'll summarize this very briefly as the classification of the briefing I received was vague. There was an encounter with a Dutch roll condition and actions taken (or not taken) to recover led to the vertical fin being overloaded and it snapped off in flight. That's all I really feel comfortable saying at this point.

Yuck.

Thanks for the information. Hopefully we'll see something public eventually.



Restoring Penn State's transportation heritage...
User currently offline135mech From United States of America, joined Oct 2006, 412 posts, RR: 4
Reply 122, posted (1 year 1 month 3 weeks 6 days 21 hours ago) and read 20744 times:
Support Airliners.net - become a First Class Member!

Quoting KC135Hydraulics (Reply 120):
Well I just got the spiel! I'll summarize this very briefly as the classification of the briefing I received was vague. There was an encounter with a Dutch roll condition and actions taken (or not taken) to recover led to the vertical fin being overloaded and it snapped off in flight. That's all I really feel comfortable saying at this point.

Hi, thanks for the update! Sad!

135Mech


User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 123, posted (1 year 1 month 3 weeks 6 days 12 hours ago) and read 20690 times:

Quoting KC135Hydraulics (Reply 120):
Well I just got the spiel! I'll summarize this very briefly as the classification of the briefing I received was vague.

I appreciate your sensitivity to releasing discretionary information.

I am a little mystified as to why the results of this accident have not been more widely distributed and discussed. Without addressing the specifics of the accident, perhaps those who have been briefed in an official capacity can share what they were told about discussing the accident and why they think there is such a deafening silence about it.


User currently offlinecargotanker From United States of America, joined Oct 2009, 164 posts, RR: 1
Reply 124, posted (1 year 1 month 3 weeks 6 days 11 hours ago) and read 20688 times:

I also have questions about why it has taken so long.

For the 2010 C-17 crash in Alaska, the accident occurred on 28 July 2010 and the public release of the AIB report occurred on 12 Dec 2010, a delay of 4.5 months.

We're currently 5 months past the accident in Manas.

The safety report was released for a short time but then rescinded. I don't know if it has been re-released.

When I read the safety report I did feel that there were some omissions and gaps in the report, I wonder if some AMC senior leaders reached the same conclusion and told the safety board to try again.

I'm currently not actively flying in the AF so I do not know if the lessons learned from the accident have been incorporated into KC-135 manuals or training. I would hope so.


User currently offlinerfields5421 From United States of America, joined Jul 2007, 7607 posts, RR: 32
Reply 125, posted (1 year 1 month 3 weeks 6 days 8 hours ago) and read 20621 times:

Quoting cargotanker (Reply 124):
For the 2010 C-17 crash in Alaska, the accident occurred on 28 July 2010 and the public release of the AIB report occurred on 12 Dec 2010, a delay of 4.5 months.

The data learned from that investigation revealed what happened conclusively and was very easy to develop from the various sources.

This crash might be a bit more difficult to identify solid data for the conclusions.


User currently offlinezanl188 From United States of America, joined Oct 2006, 3566 posts, RR: 0
Reply 126, posted (1 year 1 month 3 weeks 6 days 7 hours ago) and read 20616 times:
Support Airliners.net - become a First Class Member!

Quoting rfields5421 (Reply 125):
This crash might be a bit more difficult to identify solid data for the conclusions.

USAF aircrew are already being briefed on the investigations conclusions - the safety end of the investigation has been wrapped up. I suspect the legal end of things is ongoing and that's why the report has not been made public.



Legal considerations provided by: Dewey, Cheatum, and Howe
User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 127, posted (1 year 1 month 3 weeks 5 days 21 hours ago) and read 21034 times:

What's eery for me is that my base's QA chief was deployed to Manas during this event. He had breakfast with the incident crew that day it happened (just before their flight), and a few days later unfortunately had to lead a team to the crash site to search for various things.. it really hits home when you know someone so closely involved with the situation.

To make it even more eery, another friend of mine flew into his deployment at Manas with the incident crew a day or two before it occured. To make it even creepier, I worked on this aircraft extensively while deployed to Al Udeid early this year. 8887! It was had a lot of maintenance issues but nothing related to the rudder system from what I can recall.


User currently offlinechecksixx From United States of America, joined Mar 2005, 1137 posts, RR: 0
Reply 128, posted (1 year 1 month 3 weeks 5 days 16 hours ago) and read 20986 times:

Well having sat in a 117 that went down, and then enduring the subsequent questioning, I can say they certainly cover all the bases prior to releasing a definitive cause. Perhaps they still have more to learn and just released safety information to crews in the interim.

User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 129, posted (1 year 1 month 3 weeks 3 days 9 hours ago) and read 20472 times:

Quoting KC135Hydraulics (Reply 120):
There was an encounter with a Dutch roll condition and actions taken (or not taken) to recover led to the vertical fin being overloaded and it snapped off in flight.

If an accident cause is beginning to appear to be 'pilot error', the USAF AIB brings in a lot of legal people. The possibility of the surviving family bringing a law suit against the AIB conclusions, and or the OEM, in this case Boeing, is high.

This has been the procedure in accident investigations since the November 1982 F-16 crash near Kunsan AB, ROK. That board originally ruled the pilot, Capt. Ted Harduvel caused the accident. He could not eject because he was inverted at low altitude and crashed into a mountain while inverted. The cause was later found to be a quality control problem at General Dynamics, who then made the F-16. There was a batch of F-16s made where longer screws were used to hold in the instrument panel, some of these screws shorted out some, or all of the electrical system.

Capt. Harduvel's family sued GD, and won some $3M-$4M, however GD appealed and got the vertic overturned by claiming they were immune because they were a government contractor building an airplane to government


User currently offlineKochamLOT From United States of America, joined Sep 2007, 301 posts, RR: 0
Reply 130, posted (9 months 2 days 2 hours ago) and read 12954 times:

The KC-135 has proven lately and often to have issues with its PCU or Rudder Power Control Unit. Investigation needs to take place into this matter and fast. It has been kept hush hush. It bothers me that the superior training the Air Force prides itself on is gone as blame for such tragedy is shifted to the pilots.

The PCU controls a myriad of functions that allow the aircraft to dampen dutch roll, protect against assymetric thrust, etc.

Investigation must be made into the new manufacturer of these PCUs. For 60 years this aircraft has not had a problem. Ironically these components are supposedly made by a new supplier after the previous manufacturer went bankrupt and is no longer making the part.

The sources that caused the chain of tragic events in this accident are still at play. More and more incidents of the aircraft entering an inadvertent and potentially irrecoverable roll have occurred. Losing control effectiveness of the aircraft and rolling places impossible aerodynamic load on the entire aircraft which serves to snap airfoils and engines off of what would normally be a fully functional tanker. The vigilance of crews are required so take quick action if they are to maintain safety. Unfortunately this information was not available to the crew of Shell 77 - they are now the evidence to the issue that remains today and the reason why crews are more vigilant.

At an airline, this type of situation would have had the FAA halt all operations and investigate. In the case of the USAF, if such things were to happen, can you imagine the consequences of US Air-power? Neither can I. With new tankers on order though - where is the incentive to investigate further. It is much easier to blame the crew, one that cannot defend themselves in a court of law - because they are dead.


User currently offlineAWACSooner From United States of America, joined Jan 2008, 1950 posts, RR: 1
Reply 131, posted (9 months 1 day 19 hours ago) and read 12747 times:

Quoting KC135Hydraulics (Reply 127):

You're telling me...I took gas from this jet at least four times in Afghanistan over the past few years.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 132, posted (8 months 4 weeks 1 day 23 hours ago) and read 12070 times:

Quoting AWACSooner (Reply 131):
The KC-135 has proven lately and often to have issues with its PCU or Rudder Power Control Unit. Investigation needs to take place into this matter and fast. It has been kept hush hush. It bothers me that the superior training the Air Force prides itself on is gone as blame for such tragedy is shifted to the pilots.

As a person who changes PCUs, I must say that this has not been my observation. Prior to the Shell-77 crash I *maybe* touched 2 PCUs a year. Immediately following the crash, everyone got gun-shy about any sort of uncommanded movement and supervision was quick to pull the trigger on the PCU. My friend who just returned from Al Udeid told me he changed 7 PCUs in 4 months while there, and to be completely honest that is simply ridiculous.

People are quick to blame everything on the PCU these days when a lot of the upsets could probably be attributed to almost anything else (IE wake turbulence, autopilot anomolies, etc). Give it another year and everything will return to normal as it should.


User currently onlinekanban From United States of America, joined Jan 2008, 3756 posts, RR: 27
Reply 133, posted (8 months 4 weeks 1 day 20 hours ago) and read 11992 times:
Support Airliners.net - become a First Class Member!

Quoting KC135Hydraulics (Reply 132):
Al Udeid told me he changed 7 PCUs in 4 months while there, and to be completely honest that is simply ridiculous.

reminds me of a study where some equipment was put into two maintenance routines.. one group got none, the other maintained by policies, procedures and manual recommendations. The non-maintained out lasted the extensively maintained by 12-18 months..

the problem comes with every change out, something can fail that would have been stable if left alone.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 134, posted (8 months 4 weeks 1 day 19 hours ago) and read 11966 times:

Quoting kanban (Reply 133):
the problem comes with every change out, something can fail that would have been stable if left alone.

I have a good example of that. Every ISO (2 year interval) there is a carded item to operate the engine hydraulic shutoff valves with the T-handle and another shutoff switch down near the copilot's knee. After we operate the valves, within a day or two, at least one of them starts leaking heavily. Those shutoff valves are hardly ever operated (except for abnormal/emergency situations like a pump pressure light or engine fire) and they remain in one position for years. When we get to them, we are required to operate them to ops-check them but the disturbance causing them to go bad. If we left them alone they'd never leak... but then you don't know if they work.. it's a catch-22.


User currently offlinecjg225 From United States of America, joined Feb 2013, 873 posts, RR: 0
Reply 135, posted (8 months 4 weeks 1 day 12 hours ago) and read 11871 times:

Quoting kanban (Reply 133):
the problem comes with every change out, something can fail that would have been stable if left alone.

As KC135 says above, though, you can't just assume something will continue to work if you're not periodically checking it, especially if it is a rarely-used item that is critical in specific situations.

I get what you're saying, though. I am not a fan of doing certain kinds of maintenance or checks because I firmly believe that more fiddling by human hands can actually cause a failure or breakdown in some situations.



Restoring Penn State's transportation heritage...
User currently onlinekanban From United States of America, joined Jan 2008, 3756 posts, RR: 27
Reply 136, posted (8 months 4 weeks 1 day 7 hours ago) and read 11738 times:
Support Airliners.net - become a First Class Member!

Hydraulics are especially vulnerable, have seen cases where a pinched O-ring put a piece of material a little bigger than a head of a pin into the fluid . the piece ended up blocking a actuator metering port a couple weeks later.

Have heard of cases where not having replacement O-rings, the old were reused.. and leaked.

Quoting cjg225 (Reply 135):
As KC135 says above, though, you can't just assume something will continue to work if you're not periodically checking it, especially if it is a rarely-used item that is critical in specific situations.

While I can agree in principle, there are system functional checks that should alert one to a problem without removal. If the check indicates borderline performance, and the rest of the system is intact and functioning, then yes pull it.


User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 137, posted (8 months 3 weeks 3 days 3 hours ago) and read 10867 times:

Quoting KochamLOT (Reply 130):
The KC-135 has proven lately and often to have issues with its PCU or Rudder Power Control Unit. Investigation needs to take place into this matter and fast. It has been kept hush hush.
Quoting KC135Hydraulics (Reply 132):
As a person who changes PCUs, I must say that this has not been my observation. Prior to the Shell-77 crash I *maybe* touched 2 PCUs a year. Immediately following the crash, everyone got gun-shy about any sort of uncommanded movement and supervision was quick to pull the trigger on the PCU. My friend who just returned from Al Udeid told me he changed 7 PCUs in 4 months while there, and to be completely honest that is simply ridiculous.

There is no wide spread problems with the PCU. But that is not to say one individual PCU cannot have a problem. I believe the PCU was a contributing factor in the loss of 63-8877, but it was a problem unique to that event and that airplane. That said, the AIB has always been quick with a "pilot error" conclusion to most accidents. You can find a crew or pilot error in just about any accident, but how much of that error contributed significantly to the accident can be debated.

There are many occasions when it is wise to deviate from the book or the procedure. This is accepted up to the point of an accident. Then the AIB has a ready made excuse to rule the accident cause was pilot error.


User currently offlineKochamLOT From United States of America, joined Sep 2007, 301 posts, RR: 0
Reply 138, posted (8 months 3 weeks 1 day 22 hours ago) and read 10561 times:

Quoting KC135Hydraulics (Reply 132):
My friend who just returned from Al Udeid told me he changed 7 PCUs in 4 months while there, and to be completely honest that is simply ridiculous.

The aircrew that fly the aircraft do not tell MX how to fix the problem.

Quoting KC135Hydraulics (Reply 132):
The KC-135 has proven lately and often to have issues with its PCU or Rudder Power Control Unit. Investigation needs to take place into this matter and fast. It has been kept hush hush. It bothers me that the superior training the Air Force prides itself on is gone as blame for such tragedy is shifted to the pilots.

That is exactly right. Mx has stated that there is a new manufacturer for these PCU's and I have looked into it as much as I could. Mx I spoke with do not know who is the current manufacturer. Looking at other examples, it is an issue that is not very predictable. Case in point - the 737. A workhorse of the American domestic airline fleet at almost any airline suffered this exact issue. The manufacturer was Parker Hannifin. It appears that the KC-135 also is supplied by this same supplier but I do not know if this is a new or old supplier.

It is easy to replace a PCU or to take the aircraft on an operational check flight - and call it good. What is happening now with the KC-135 does need further investigation. Checklists offer pilots a flow chart of methods to detecting what might be wrong - at this point you are more than just a military pilot - you are a test pilot.

At the Deid: a copilot friend and the DO flew a sortie of refueling over the Stan when on return during cruise, the aircraft rolled into a 30 degree bank in 2 seconds. Thankfully the daylight provided the natural horizon to the pilots to realize what was truly happening. The aircraft (Alaska tail) just sat on the ramp for weeks. Apparently it is flying again. A similar situation happened again (Feb '14) and the crew diverted to Shannon. The PCU on this particular jet had just been completely replaced prior to the return from the Deid. 600 miles off the coast and the aircraft experienced this uncommanded phenomenon to which the crew responded and was blessed to make it back. We dont need more examples / dead airmen to prove a point.


User currently offlineKochamLOT From United States of America, joined Sep 2007, 301 posts, RR: 0
Reply 139, posted (8 months 3 weeks 1 day 22 hours ago) and read 10555 times:

Quoting KC135TopBoom (Reply 137):
There is no wide spread problems with the PCU. But that is not to say one individual PCU cannot have a problem.

That is correct. An example I found quite interesting:
http://www.aerohabitat.eu/uploads/me...Remembering_flight_427__1.5MB_.pdf

I would agree that in response to Shell 77 crews are more alert and sensibly quite sensitive to the issue. No aircraft should inadvertently roll into 30 degrees of bank, or with A/P off and with increasing amplitude roll into 15 degrees of bank uncommanded from side to side... if this was the case at American, Delta or United, the FAA would have a field day and passengers would not be amused.

Pilots fly, data is analyzed and when these things happen they are to be fixed. If a new PCU is not required, then yes it would be moronic to fix or replace it if it was not found causal.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 140, posted (8 months 3 weeks 1 day 20 hours ago) and read 10537 times:

Kocham, I am not sure of your credentials so if I am telling you something you already know, forgive. You're right, pilots don't tell us how to fix their aircraft, but often times our maintenance supervision likes to tell the maintainers how to do it, even if they are completely unfamiliar with the system. My case in point is the 7 PCU changes my coworker just endured. There are testing/isolation procedures that can be done on a PCU to determine serviceability. Even when these PCUs tested good and exhibited no signs of malfunction or damage, the supervision was directing the part(s) to be changed regardless, despite the best objections of the technicians and subject-matter-experts involved. I feel, as does everyone else in my line of work, that this was a direct result of the crash last year and was driven more by a sense of paranoia than anything else.

User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 141, posted (8 months 2 weeks 6 days 7 hours ago) and read 10116 times:

The long awaited announcement. Full details to be released Monday. The Air aforc conclusion was that it was a preventable accident.

http://krem.mlnwap.com/article.html#...1/8a84eda89663b0ea21d6dd7da81d5fbf



OMG-Obama Must Go
User currently offlinebuckeyetech From United States of America, joined Jul 2013, 55 posts, RR: 0
Reply 142, posted (8 months 2 weeks 4 days 15 hours ago) and read 9831 times:

So the report was released. This raises more questions than it does answers. I hope they produce a computer generated video of what happened as a visual aid.

http://www.stripes.com/news/air-forc...d-3-1.272631#.UyPAIFGZ6Ao.facebook



B-52H, C-141C, C-5A, C-17A
User currently offlinewindy95 From United States of America, joined Dec 2008, 2749 posts, RR: 8
Reply 143, posted (8 months 2 weeks 4 days 12 hours ago) and read 9741 times:

Quoting buckeyetech (Reply 142):
This raises more questions than it does answers..

Like?



OMG-Obama Must Go
User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 144, posted (8 months 2 weeks 4 days 7 hours ago) and read 9708 times:

I would like to see the report and find out precisely what induced the dutch roll to begin with. Was it a failure of the series yaw damper?

User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 145, posted (8 months 2 weeks 4 days 5 hours ago) and read 9671 times:

Quoting KC135Hydraulics (Reply 144):
I would like to see the report and find out precisely what induced the dutch roll to begin with. Was it a failure of the series yaw damper?

From the news release:

A bent lock lever in the power control unit caused the initial slow, erratic
drifting, which soon grew into a dangerous "Dutch roll" of the plane --
rocking side to side and pitching up and down, according to the report.

I actually haven't seen the final report for specific technical details.

Quoting buckeyetech (Reply 142):
This raises more questions than it does answers. I hope they produce a computer generated video of what happened as a visual aid.

I think the report is pretty straightforward. What specific unanswered questions do you have in mind?


User currently offlinebuckeyetech From United States of America, joined Jul 2013, 55 posts, RR: 0
Reply 146, posted (8 months 2 weeks 4 days 4 hours ago) and read 9653 times:

Quoting windy95 (Reply 143):
Like?
Quoting rc135x (Reply 145):
I think the report is pretty straightforward. What specific unanswered questions do you have in mind?

I guess the biggest question I have is, what initially caused the crab? Was it the autopilot computer, or the wake of another aircraft? What is the proper procedure for recovering from a Dutch roll?



B-52H, C-141C, C-5A, C-17A
User currently offlinerc135x From , joined Dec 1969, posts, RR:
Reply 147, posted (8 months 2 weeks 4 days 4 hours ago) and read 9676 times:

Quoting buckeyetech (Reply 146):
what initially caused the crab? Was it the autopilot computer, or the wake of another aircraft? What is the proper procedure for recovering from a Dutch roll?

A bent component on the rudder power control unit (PCU) caused abnormalities in rudder operations for 14 missions prior to the crash. On the day of the crash the rudder reached a point where it induced a natural phenomenon in swept wing jets known as Dutch Roll, a waffling oscillation of the plane in yaw and roll.

When that happens, the flight manual is very clear (despite what the accident report suggests): Turn OFF the powered rudder. Do NOT use the autopilot. Maintain aircraft control.

The crew failed to do all three of these. They failed to execute the BOLDFACE for rudder failure in flight (RUDDER POWER --- OFF), they engaged the autopilot to try to stop the increasing amplitude of Dutch Roll, and they started yapping on the radio instead of flying the airplane. Moreover, they forgot to pull the power back from climb setting, allowing the jet to increase airspeed to 320 KIAS instead of slowing it to 240 KIAS or so to restore stability. At that point, the airplane tore itself apart.

This was a case of a part that broke and the crew did everything wrong.


User currently offlineKC135Hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 148, posted (8 months 2 weeks 3 days 7 hours ago) and read 9483 times:

I'll have to get into my TOs but I am wondering if it was the tab lockout that was bent. That's the only lockout I'm familiar with on the PCU. I'll take a look and see what's doing for those who aren't privy to the final report, which I am certain precisely identifies the malfunctioning component of the PCU.

User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 149, posted (8 months 1 week 5 days 3 hours ago) and read 9027 times:

Quoting rc135x (Reply 147):
A bent component on the rudder power control unit (PCU) caused abnormalities in rudder operations for 14 missions prior to the crash. On the day of the crash the rudder reached a point where it induced a natural phenomenon in swept wing jets known as Dutch Roll, a waffling oscillation of the plane in yaw and roll.When that happens, the flight manual is very clear (despite what the accident report suggests): Turn OFF the powered rudder. Do NOT use the autopilot. Maintain aircraft control.The crew failed to do all three of these. They failed to execute the BOLDFACE for rudder failure in flight (RUDDER POWER --- OFF), they engaged the autopilot to try to stop the increasing amplitude of Dutch Roll, and they started yapping on the radio instead of flying the airplane. Moreover, they forgot to pull the power back from climb setting, allowing the jet to increase airspeed to 320 KIAS instead of slowing it to 240 KIAS or so to restore stability. At that point, the airplane tore itself apart.This was a case of a part that broke and the crew did everything wrong.

Back in my KC-135A/Q days, we did not have a yaw damper on the airplane. The autopilot had a rudder axis, and we had the powered rudder (added as part of the Pacer Fin program). Pilots were trained in dutch roll mitigation and practiced it in the airplane (until simulators got better). Turning off the powered rudder was always the first step. If needed then turn off the A/P rudder axis. Our pilots back then were great "stick and rudder pilots".

The KC-135E was the first model with a yaw damper, but some RC-135 models had them for years before the KC-135E.

But our worst rudder failure mode, I believe was a hard-over rudder on short final. The pilot had to react quickly to save the airplane and crew.


User currently offlinekochamLOT From United States of America, joined Sep 2007, 301 posts, RR: 0
Reply 150, posted (7 months 3 days 18 hours ago) and read 6771 times:

Quoting rc135x (Reply 147):
On the day of the crash the rudder reached a point where it induced a natural phenomenon in swept wing jets known as Dutch Roll, a waffling oscillation of the plane in yaw and roll.

When that happens, the flight manual is very clear (despite what the accident report suggests): Turn OFF the powered rudder. Do NOT use the autopilot. Maintain aircraft control.

The crew failed to do all three of these. They failed to execute the BOLDFACE for rudder failure in flight (RUDDER POWER --- OFF), they engaged the autopilot to try to stop the increasing amplitude of Dutch Roll, and they started yapping on the radio instead of flying the airplane. Moreover, they forgot to pull the power back from climb setting, allowing the jet to increase airspeed to 320 KIAS instead of slowing it to 240 KIAS or so to restore stability. At that point, the airplane tore itself apart.

This can be confirmed by someone else, but supposedly, the primary means of addressing Dutch Roll is engaging the SYD - series yaw damper. The SYD relied on the then-malfunctioning component of the aircrafts flight controls. BAck in the A model days, crews were trained to deal with Dutch Roll because they did not have the technologies that were later installed. Dutch roll was a factor and pilots were trained for it then. When the CFMs became the new engine, a greater risk was posed by the immensely more powerful engines - an engine out procedure with the new engines posed greater risks compared to the meagerly powered trubojet eninges. To combat OEI scenarios with the new jets, systems were installed. With the installation of the SYD and the installment of the FCAS FLight control augmentation system - pilots were not exposed to the same training and the same training materials regarding aerodynamic phenomena such as Dutch Roll were slowly phased out of the training curriculum. Today, a discussion on Dutch Roll is the norm.

So yes, Dutch roll was there and yes the pilots had exacerbated the situation - a scenario of which the USAF has not invested much attention to after the retrofitting of 'new' FCAS components. ALSO, the aircraft did not roll into an incredibly noticeable bank that would have been a clear boldface-type situation. The aircraft was not handling 'normally' - the plane was 'waffling'.. and troubleshooting occurred. Faulty source information from ADCs can be swapped and checked for AP operation and no, probably not the great idea of the day. In a very finite amount of time the crew kicked the AP off and hand flew the jet and attempted to turn back but it was too late. Supposedly the pilot played with the Rudder thereby worsening the dutch roll. As roll increased with the increase in dutch roll the aircraft subsequently entered a nose low attitude and breakup began before impacting terrain.

Rudder malfunctions in the past have most often been very deadly. rc135x - you mention that they 'forgot' to slow down.
Looking at some other cases involving similar rudder incidents, speed actually helped. Reference Eastwind 517 - http://community.seattletimes.nwsour...rchive/?date=19960703&slug=2337561

A Boeing 707 and Boeing 720 both suffered a similar Rudder issue. The 707 - an AA flight out of New York rolled inverted on departure climb out. Boeing 720 was conducting a flight check when at a slow speed on approach to landing, the aircraft rolled inverted and crashed due to a Rudder anomaly. USAIR 737 at Pittsburgh and a United 737 crash in Colorado also due to Rudder issues. The high visibility of these accidents brought about changes. I came across some finding that are very interesting regarding the 737 Rudder issues. http://lessonslearned.faa.gov/USAir427/usa427%20ntsb%20findings.pdf

And finally, a nearly nonexistant story (from a newsmedia perspective) was the proper conduct of a no-kidding hardover rudder incident on a Northwest 747 - aircraft was level at FL350 when the jet suddenly and on its own rolled quickly into what was apparently 17+ degrees contintuing to 32 degrees of bank. Pilots used assymetric thrust to divert to the nearest airfield in Alaska. http://www.ntsb.gov/aviationquery/br...018X05344&ntsbno=ANC03IA001&akey=1

You can thank the tempo and the way of the USAF to place crew not properly trained for such events or of low experience levels to deal with a malfunction such as the one presented in Shell 77. AIB reported that there is no such training even in the simulators that could replicate what the crew of Shell 77 experienced. It is so easy to point a finger. Maintain aircraft control, Analyze the situation and take proper action - becomes a little more conflicted when the issue you need to analyze is the flight controls themselves that help or hurt your maintenance of that control. Making sure you have a safe jet to begin with is also crucial - keeping an aircraft that creates a chain of negative circumstances - latent errors that present themselves into the active error - the resulting loss of control and breakup of the shell 77 shortly after departure.


User currently offlineSTOOBIE From United States of America, joined Sep 2013, 10 posts, RR: 0
Reply 151, posted (6 months 2 weeks 2 days 3 hours ago) and read 5472 times:

For the Aero/Docks guys, check your tab and trim control rods. We had balooning of the metal causing a fissure to open up the trim contol rod. Water seems unlikely at this point but we're still looking.

User currently offlineKc135hydraulics From United States of America, joined Nov 2012, 322 posts, RR: 0
Reply 152, posted (6 months 1 week 18 hours ago) and read 4514 times:

Quoting STOOBIE (Reply 151):
For the Aero/Docks guys, check your tab and trim control rods. We had balooning of the metal causing a fissure to open up the trim contol rod. Water seems unlikely at this point but we're still looking.

It's coincidental that you mention that. We have a plane in ISO right now with a write-up for some hardware out of sorts on the PCU. I'll probably be going up to look at it sometime Tuesday so I'll take a look at that stuff while I'm there. Could you be more specific as to the areas of the control rods that need attention?


Top Of Page
Forum Index

Reply To This Topic KC-135 Crash In Kyrgyzstan
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Military aviation related posts only!
  • Not military related? Use the other forums
  • No adverts of any kind. This includes web pages.
  • No hostile language or criticizing of others.
  • Do not post copyright protected material.
  • Use relevant and describing topics.
  • Check if your post already been discussed.
  • Check your spelling!
  • DETAILED RULES
Add Images Add SmiliesPosting Help

Please check your spelling (press "Check Spelling" above)


Similar topics:More similar topics...
KC-135 Lands With Refueling Boom Down posted Sat Apr 28 2007 02:34:48 by AirTranTUS
KC-135 Tanker Wing posted Sat Jan 6 2007 01:17:13 by Blackbird
KC-135 Will Be Sold To Israel posted Fri Apr 19 2013 13:44:27 by An225
Utah Air Guard KC-135 Refueling Mississippi C-17 posted Tue Jan 15 2013 12:41:05 by flynlr
Russia Loses Contact With Its Satellites posted Wed Nov 14 2012 11:26:47 by MadameConcorde
Fake Chinese Parts On US Military Aircraft posted Tue May 22 2012 11:42:09 by chuchoteur
3 KC-135's At TPA 1/31 posted Tue Jan 31 2012 19:35:09 by tpa36r
Drone Tanker Aircraft? posted Sat Nov 26 2011 07:35:04 by HaveBlue
Why Letter "K" In KC-135? posted Sun Nov 20 2011 11:37:43 by haynflyer
KC-135 At EDDH/Hamburg posted Tue May 31 2011 01:08:56 by BizFlyer
Crash In Afghanistan posted Tue Feb 11 2014 07:25:05 by bennett123
Time On MC-12W Crash In Afghanistan posted Wed Oct 30 2013 10:03:35 by SSTeve
ERB-47H Crash In Iran Circa 1967 posted Mon Oct 21 2013 12:01:33 by rc135x
KC-135 Tail Marking? posted Sun Aug 4 2013 10:02:33 by UltimateDelta
Proton-M Rocket Crash In Kazakhstan posted Tue Jul 2 2013 01:41:42 by MadameConcorde
KC-135 Required Runway Length posted Wed Jun 26 2013 06:42:48 by tsra

Sponsor Message:
Printer friendly format