GEEDO From United States of America, joined Feb 2004, 366 posts, RR: 0 Posted (9 years 9 months 2 weeks 1 day 17 hours ago) and read 3658 times:
Whenever our local Air Guard F-15's or other fighters that may be visiting here at PDX, get clearance from the tower to takeoff, they are always told that "The departure cable indicates up". They are also advised that the "cable is up" when they receive clearance for final approach. I have had a few explanations given for what this refers to, but I suspect it is mostly amateur's speculation. Can somebody give me the real word on what the cable reference really means? Is it a real cable raised on the tarmac? Something only seen or used by the ATC's? All responses are greatly appreciated.
Should this have been in the military forum?
Avioniker From United States of America, joined Dec 2001, 1109 posts, RR: 11 Reply 1, posted (9 years 9 months 2 weeks 1 day 4 hours ago) and read 3506 times:
There is an arresting cable stretched across both ends of the runway. Just like an aircraft carrier. The designation is BAK-9/12 or whatever the system model designation is that's in use at that airfield.
Fighter aircraft have a hook on the tail which the pilot may lower in the event of an emergency which will catch the cable and stop them quickly.
If the departure end cable across the runway is left in the raised position and the aircraft rolls over it at that high speed on takeoff it may upset the balance of the aircraft and become a BIG problem.
The cable at the departure end of the runway is normally lowered into a trough so that upset doesn't occur.
If you or the pilot are informed that the Departure Cable is up that means you need to be airborne before you get there.
You can tell where the cables are installed by looking for a large black square sign with a large orange circle (3 feet in diameter) in the center at both sides of the runway on both ends of the cable.
One may educate the ignorance from the unknowing but stupid is forever. Boswell; ca: 1533
Mr Spaceman From Canada, joined Mar 2001, 2786 posts, RR: 9 Reply 2, posted (9 years 9 months 2 weeks 1 day 1 hour ago) and read 3457 times:
> GEEDO, I think this post could be in either form, so I believe it's fine here.
I did a photo search and found this picture at Portland Intl (PDX), which shows a large orange ball in the background (left of the 767's engine). It's not an orange circle on a black square, it's an actual round ball that looks to be about 3 feet in diameter, so it must be what Avioniker is talking about. I've never noticed one of these before. This is neat to learn about.
Corey07850 From United States of America, joined Feb 2004, 2525 posts, RR: 5 Reply 5, posted (9 years 9 months 2 weeks 22 hours ago) and read 3412 times:
The red/gray object you asked about looks like a wind shear detector to me. They generally look like those tennis ball shooter machines and are scattered around the airport. Each station detects wind direction and speed, and airport ops look for major differences in wind directions and/or speed.
Mr Spaceman From Canada, joined Mar 2001, 2786 posts, RR: 9 Reply 6, posted (9 years 9 months 2 weeks 22 hours ago) and read 3410 times:
Thanks for your info about that red & grey object at PDX. It does look like a tennis ball shooter. I'll have to look around the airfield for them the next time I'm out at Toronto Intl (YYZ).
I've heard the ATIS for YYZ report the different windspeeds & directions for the different quadrants of the airport. I think this is only done when the winds are quite variable, and I'd guess it's an automated system.
GEEDO From United States of America, joined Feb 2004, 366 posts, RR: 0 Reply 7, posted (9 years 9 months 2 weeks 18 hours ago) and read 3375 times:
Yes, I saw the orange balls today. I think they were even illuminated from inside. I noticed this because there was a heavy downpour when I was out there and visibilty was low.
Mr. Spaceman: I don't think the northern runway has it. The south runway is the longer of the two and used almost exclusively for military operations. I say almost because I have been witness to a few exceptions.
I wondered about those "tennis shooter" things as well. I used to think they were static, but I've seen them rotate. I also had the notion they were part of the wildlife dispersal system, as I could have sworn I heard them give out a loud "POP" of compressed air or something. Just uneducated speculation, my thanks again to all with the corrections!
Yes, F-15s do have a hook. It is right in between the two engines like an F-18. Most Eagles that I have seen usually have wear marks on theirs as if they had been used. Hydraulic failures, while not common, happen often on the old A models of the Missouri ANG. Many airports that have military ops have arresting gear of some kind. You can find out what kind in the Airport/Facilities Directory (AF/D).
Being where these things are built, I've seen a couple aircraft snag the wire, it's way cool! It stretches out for a while to gradually decelerate the aircraft.
AAR90 From United States of America, joined Jan 2000, 3434 posts, RR: 49 Reply 10, posted (9 years 9 months 2 weeks 7 hours ago) and read 3331 times:
I don't think the northern runway has it.
Not indicated on my Jepp charts, which show 10R/28L as having two bidirection arresting cable installations.
Yes, F-15s do have a hook.
Early models did not come with a tailhook, which was an option added later.
...usually have wear marks on theirs as if they had been used.
If it is not ground down, it was not "used." Probably lowered for system check, but a single field "trap" will grind down a considerable amount off the hook "point."
...I've seen a couple aircraft snag the wire, it's way cool! It stretches out for a while to gradually decelerate the aircraft.
Booorrrriiiinnnngggg. Oh sorry, probably not for you landlubbers. Once diverted off Big-E and took a last minute field trap at Miramar. The 4 other aircrew were all excited since they had never done that before. All 4 were sadly disappointed as it truly is boring event for an experienced "tailhooker." Normally about 1/4 the stopping force of a CV's arresting gear = very boring.
*NO CARRIER* -- A Naval Aviator's worst nightmare!
OPNLguy From , joined Dec 1969, posts, RR: Reply 11, posted (9 years 9 months 2 weeks 3 hours ago) and read 3290 times:
>>>I wondered about those "tennis shooter" things as well. I used to think they were static, but I've seen them rotate. I also had the notion they were part of the wildlife dispersal system, as I could have sworn I heard them give out a loud "POP" of compressed air or something. Just uneducated speculation, my thanks again to all with the corrections!
They are devices to scare away the birds. I was on a cockpit jumpseat ride into BHM and noticed some at the approach end of runway 6, and I called the tower to ask. If they see birds congregating, they trigger the thing remotely, and away go the birds (for awhile, anyways).
AAR90 From United States of America, joined Jan 2000, 3434 posts, RR: 49 Reply 13, posted (9 years 9 months 1 week 6 days 22 hours ago) and read 3239 times:
All 15's had hooks but the problem came in 72 and 73 when 291 did the tests at EDW and the hook came out. 085, 086, 087, 108 and 109 were all delivered to the Nickel with hooks in 74.
Very interesting. We had a number of -15s out to Miramar for Topgun sessions during early 1980s and none of them had tailhooks... we even had to remove the cross-deck pennants since the USN ones do not retract into the ground ala the BAK-xx designs. The -15 pilots said the early models didn't have tailhooks, which is where I got my obviously incorrect info from.
*NO CARRIER* -- A Naval Aviator's worst nightmare!
Dc10hound From United States of America, joined Dec 2000, 463 posts, RR: 6 Reply 15, posted (9 years 9 months 1 week 6 days 18 hours ago) and read 3198 times:
I just dug this out of the archives. I just knew I saved this for some reason. I hope it might of interest to you guys...
Excerpt from the F-15C/D "Dash One" Checklist:
USAF T.O. 1F-15C-1CL-1 (Page E-34)
LANDING GEAR EMERGENCY - LANDING
Before Attempting Landing, Consider: Arresting Gear Limitations
Runway and Overrun Condition
If Considerations Not Favorable - EJECT
1. Jettison Armament (Consider Retaining Racks)
2. Dump or Burn Excess Fuel
3. Retain Empty External Tanks (Depressurize - Open Slipway)
4. Flaps - Down
5. Fly 18 Units AOA With Flat Approach
LANDING NOT RECCOMENDED
One Main - No Nose
Retract Gear and Refer to All Gear Up
If Gear Will Not Retract
- Recommend EJECT
ARRESTMENT NOT RECCOMENDED
All Gear Up 1
- 170 Knots Touchdown Speed
Both Main - No Nose
Do Not Shutdown Engines Until Stopped
APPROACH END ARRESTMENT RECCOMMENDED
No Main - Nose Down
Jettison C/L Tank
If Arrestment Not Practicable:
- Do Not Shutdown Engines Until Stopped
One Main - Nose Down
If Arrestment Not practicable
- Retract Gear and refer to All Gear UP
If Gear Will Not Retract
- Recommend EJECT
We had a Pilot flying an Eagle out of Bitburg with the last configuration. He landed the aircraft. Damaged was limited to the centerline tank and wing tip.
Note that the checklist says recommend Ejection.
He told me that he airplane was flying perfectly fine except for the gear detail.
Why should he jump out of it?
I have more info on BAK 9-12 Engagement Speeds/Weights
"Eagles soar. But weasels never get sucked into jet intakes.."
Contact_tower From Norway, joined Sep 2001, 536 posts, RR: 1 Reply 17, posted (9 years 9 months 1 week 6 days 4 hours ago) and read 3136 times:
"do airliners have the chance to arrest the cable sometimes? That's insane! "
Well, we have our arresting systems on the overrun to each runway, so it is not a factor. However, we have experienced that aircraft including a 737 have landed short of the threshold snagging the cable with the main landing gear, dragging it for a few feet before it let go.
(It completely thrashed the AAB34B-1C, it's not designed to arrest aircraft that heavy. No damage to the 737)
No problem for the 737, they regularly take off over the cables at other airports that have them inside the threshold. Landing over one is not recomended, and not done.