Quote: Incident one occurred in August on a westbound United Boeing 767 from San Francisco to Hawaii. A pilot-trained passenger happened to notice that three hours out, the airplane made a slow 180-degree turn back toward the west coast. Shortly thereafter, a PA from the flight deck said that the aircraft had lost all navigational capability. The crew had declared an emergency, climbed to 34,500 feet for additional separation and was aiming for California. It eventually was assigned a hard altitude and landed in San Francisco without incident. As far as I know, the incident didn't make it into the news cycle. Our correspondent told us she spoke to the crew, who said they navigated home with a whiskey compass and an iPad…in a multi-million dollar airplane with a half-million dollar glass panel. All the better reason to keep a basic text on your iPad refreshing your memory of northerly compass turning error.
Can anyone here shed some more light on this incident? It looks pretty serious and I can't find any more info about this on the internet.
fr8mech From United States of America, joined Sep 2005, 4265 posts, RR: 12 Reply 1, posted (6 months 3 weeks 4 days 3 hours ago) and read 3975 times:
A triple IRS failure? Plus a dual GPS failure? Plus a triple VOR failure (when in close to the coast)? Dual ADF failure? Unless they lost all 4 screens and their RDMI's, I just can't see that happening.
The power failure that would cause all those problems would be noticed in the back.
Methinks there was more, or more probably, less to this story.
There coud be more to the story but does anybody know what plane it was?? just for Grins I could check the records but it's now November and that would be in long term history from August.
rfields5421 From United States of America, joined Jul 2007, 6150 posts, RR: 25 Reply 4, posted (6 months 3 weeks 3 days 22 hours ago) and read 3864 times:
Three hours out - the plane would be beyond range of VOR or ADF stations.
CosmicCruiser From United States of America, joined Feb 2005, 2214 posts, RR: 16 Reply 7, posted (6 months 3 weeks 3 days 16 hours ago) and read 3699 times:
3 hrs out? heck they were closer to Hawaii! Yeah I know the continent is bigger.
fr8mech From United States of America, joined Sep 2005, 4265 posts, RR: 12 Reply 10, posted (6 months 3 weeks 3 days 8 hours ago) and read 3467 times:
Quoting TWA772LR (Reply 9): Wasn't that the reason for the 737s eyebrows?
The DC8 had a sextant hole. The classic jumbos had a hole that was called the smoke evacuation port but the urban mythology amongst the maintenance folks is that is could also be used to take sightings.
Some of our older arctic B737s had a sextant hole, and those "arctic trained" had to use it on check rides. They also had an Astro Compass mount on the F/O's window!
Someone put a vacuum hose in one aircraft. One end would fit through the hole, the other end was used to clean out the cockpit!
Both an Astro Compass and a Sextant would have come in real handy if this B767 really did lose all navigation capability!
Never gonna grow up, never gonna slow down .... Barefoot Blue Jean Night
KELPkid From United States of America, joined Nov 2005, 5934 posts, RR: 4 Reply 12, posted (6 months 3 weeks 2 days 15 hours ago) and read 3299 times:
Quoting TWA772LR (Reply 9): Wasn't that the reason for the 737s eyebrows?
Nope. No way you could do star shoot from one They are there because the FAA felt the old Boeing section 41 didn't have very good visibility in the traffic pattern while turning...
Celebrating the birth of KELPkidJR on August 5, 2009 :-)
stratosphere From United States of America, joined Sep 2007, 1614 posts, RR: 4 Reply 14, posted (6 months 3 weeks 1 day 9 hours ago) and read 3044 times:
Quoting Max Q (Reply 8): They may have turned back for all number of reasons but losing all three IRS computers and two GPS receivers is highly unlikely.
Max Q From United States of America, joined May 2001, 3293 posts, RR: 19 Reply 15, posted (6 months 3 weeks 1 day 7 hours ago) and read 3007 times:
Quoting stratosphere (Reply 14):
They may have turned back for all number of reasons but losing all three IRS computers and two GPS receivers is highly unlikely.
Maybe geographically, but quite possibly not closer when factoring in headwinds. May not have passed their equal time point, thus it was quicker to turn around and head back than to continue.
fr8mech From United States of America, joined Sep 2005, 4265 posts, RR: 12 Reply 19, posted (6 months 3 weeks 17 hours ago) and read 2827 times:
Quoting avantime (Thread starter): Can anyone here shed some more light on this incident? It looks pretty serious and I can't find any more info about this on the internet.
I'm a skeptic on this incident. So, I looked at some prints and tried to make 3ea IRS fail and both GPS fail without letting the people in the back know (i.e. dual IDG failure, with a failure of the standby buss) and I can't do it.
I'm calling BS on a story that was designed to make a point about electronics on aircraft.
KELPkid From United States of America, joined Nov 2005, 5934 posts, RR: 4 Reply 22, posted (6 months 3 weeks 13 hours ago) and read 2727 times:
Quoting HAWK21M (Reply 21): Seems very difficult to believe considering the range of navigation equipment available on the B767.
I wonder if they still carry an ADF receiver, as NDB's have been decomissioned by the droves here in the US. I realize that NDB's are still pretty common overseas, but even when NDB's were still fairly common in the US, in general aviation planes, if you had a GPS onboard, it was much more convienient and simpler to navigate using GPS overlay, especially when IFR.
If you have an ADF receiver, you can at least home in on a powerful AM radio station...
I know that other long range navigation systems (like Omega/VLF and LORAN) have been supplanted by GPS and GPS alone (well, with IRS as a backup on an airliner).
Once the aircraft was within ~130 miles of the US coast, the navigation system woud have started to pick up VOR/DME (assuming that much was operable...).
Celebrating the birth of KELPkidJR on August 5, 2009 :-)
Jetlagged From United Kingdom, joined Jan 2005, 2452 posts, RR: 17 Reply 24, posted (6 months 3 weeks 12 hours ago) and read 2693 times:
Quoting SKC (Reply 17): Maybe geographically, but quite possibly not closer when factoring in headwinds. May not have passed their equal time point, thus it was quicker to turn around and head back than to continue.
Without oceanic navigation ability, the chances of finding Hawaii are remote. However head back to the east and you will certainly find land.
Quoting KELPkid (Reply 22): I wonder if they still carry an ADF receiver, as NDB's have been decomissioned by the droves here in the US.
Not too many NDBs in the Pacific, so it's a moot point. But I'd be surprised if ADFs had been removed.
Quoting fr8mech (Reply 19): I'm a skeptic on this incident. So, I looked at some prints and tried to make 3ea IRS fail and both GPS fail without letting the people in the back know (i.e. dual IDG failure, with a failure of the standby buss) and I can't do it.
What about a loss of power to the EFIS displays, so even if the IRS and GPS were functional they wouldn't be any use to steer by. I remember a 757 that happened to in Europe many years ago, but I forget the cause. They don't like heat, an equipment cooling failure could take them out.
Quoting fr8mech (Reply 19): I'm calling BS on a story that was designed to make a point about electronics on aircraft.
Maybe it was the iPad the report mentioned they navigated with that caused the problems.
The glass isn't half empty, or half full, it's twice as big as it needs to be.
25 longhauler: That's not a DC-8 .... VC-10 maybe?
26 fr8mech: I thought about that. In fact, if this is true, it's the most likely scenario. I believe the 4 screens all live on at least 3 different busses. Very
27 Jetlagged: But it has happened to at least one 757. That wasn't over an ocean so radio navigation was still possible. I forget the cause, but it was back when g
28 Max Q: As unlikely as that is you would still have a course to steer by referring to the legs page of the FMC computer. And if ADF is fitted you can steer t
29 rfields5421: While I agree in principle - what about airline SOP. At which point does United SOP consider the navigation system unreliable. When one IRS disagrees
30 zeke: What about the QF 744 incident into BKK ? A fault with the water drain in the galley caused water to go over the avionics, getting rid basically all
31 fr8mech: I'm not saying it can't happen, I'm saying that it's highly unlikely. And, it would require multiple failures. And, chances are the folks in the back
32 rfields5421: The more I think about this, the more I'm inclined to put this into the urban legend category. Not for any of the valid reasons both against or for t
33 tdscanuck: Didn't that just take down the AC buses? They would have still had hot battery, capt DC, and standby. That would give you some (though certainly not
34 zeke: UA only do 4 flights a day from SFO to HNL, it shuld be easy to check with flight aware to see if the 124 odd flights for teh month made it to HNL. U
35 KELPkid: Seems like such a failure would be reportable to the FAA, NTSB, or both...that's been my thoughts throughout the day. In which case publicly availabl
36 longhauler: Not to mention ... on the inside, this alleged event would be HUGE, and every pilot of every B757/767 would be informed and warned ... and we haven't
37 COSPN: I dont think you have to be "pilot-trained" to notice the plane has done a 180 and heading back east...
38 zeke: Can I ask then what you were told about the S7 airlines 767 incident in October that had a similar loss of navigation and diverted Venice ? I suspect
39 Starlionblue: True. However most people would not notice.
41 longhauler: I think it depends on the cause. I don't think the final report is issued yet. (If you mean the one a month ago, how did you hear about it?) There wa
42 CosmicCruiser: you bet it would be reported. nav failure in Class II airspace, absolutely.
43 zeke: For may incidents, there is never any report or investigation issued by the relevant air safety investigators. That is often left to the operator and
44 tdscanuck: That's true, but there's a huge swath of stuff in between what comes under the purview of the air safety investigators (which requires an actual or n
45 longhauler: I think you missed my point. I am not talking about any mundane "update" where procedures have changed, or responses where changed from CHECK to SET.
46 zeke: No I did not. For a while no one had information about AF447, and all sorts of speculation was about. When more information was available, it was app
47 longhauler: One of the biggest changes was the introduction of the "Loss of Reliable Airspeed" drill. It had always been an OEB, with a checklist. However, durin
48 tdscanuck: Yes. I've written those types of communications. The lawyers have no say in them whatsoever. One of the very first actions when an OEM suspects an is
49 zeke: Standard Airbus QRH has always had it as a QRH item, the memory items have always been there. Have a look at the AF447 report you can see the standar
50 rfields5421: Over the decades it proved to be an unnecessary concern, and many airlines did not want the extra expense and extra maintenance requirements of the e
51 longhauler: I only used the A330 and B737 as an example, as it shows the point I was trying to make. When there are incidents of "unusual circumstances" airlines
52 tdscanuck: It's not an accident (or incident) but it is a reportable event. If it occured, the OEM would be obligated to report it to the FAA (assuming the OEM
53 zeke: No I do not think the PCU alone was at fault, they proved to be safe for years. It took exposure to certain conditions for it to occur. You are think
54 tdscanuck: To the FAA. Because the FAA requires it. For Boeing, it's called the Continued Operational Safety Program. I believe the FAA has something similar wi
55 longhauler: Does that mean therefore, that only those within an airline (or Governmental body) that are directly associated with that aircraft type would see the
56 Viscount724: Caption said it was a DC-8. I guess it was wrong.
57 longhauler: That one has six eyebrow windows, the DC-8 only two. I was guessing the VC-10 over the IL-62, as I remembered the VC-10 had the pull shades to cover
58 Fabo: That is a VC-10 all right. Il-62, completely different game. Plus I dont think it ever had a sextant hole.
59 tdscanuck: Yew. The normal chain of events for something like this is: 1) Airline notifies OEM of event 2) OEM assesses event for reportability, safety, prior r
60 zeke: You must me talking about very minor things. For example you will see transmissions made by Airbus regarding AF447 not only had to get signed off int
61 tdscanuck: No. "Very minor things" don't meet the threshold for mandatory reporting. That was an actual accident; very different protocols involved. The situati
62 longhauler: I know this is merely anecdotal ... but I am bored here on a layover. Using the online tracking websites, I see that every UAL B767 that departed SFO
63 zeke: Hardly unprecedented when S7 and United (the earlier diversion I mentioned) had similar events recently. Also the avweb article actually was referrin
64 tdscanuck: Because the FAA requires it. I'm not sure how many times we're going to go around this circle. Only accidents and incidents have to be reported *by I
65 zeke: And all I ask is where ? Show me the FAA regulation/order that requires an operator to report maintenance defects to an OEM. The operators are requir
66 tdscanuck: FAR 21.3, Reporting of Failures, Malfuctions, and Defects http://www.ecfr.gov/cgi-bin/text-idx...t&node=14:1.0.1.3.9.1.11.3&idno=14 This part
67 26point2: Funny what people will believe. These iPad-saved-the-day stories are ridiculous. Not sure if this has been mentioned....These events suposedly occurre
68 longhauler: This is something that also had my head scratching. Flight plans today are so accurate, it is eerie! I have left YYZ for a 10 hour flight to TLV, and
69 Jetlagged: Given the choice between either (a) trusting in winds aloft predictions (made several hours ago) plus dead reckoning, to aim at a group of islands or
70 longhauler: I know this is all "what if" conjecture, and great cockpit puzzle during slow times, but ... my two cents, which is in absolutely no way correct. Toda
71 zeke: Yep That I agree with. Yep, all that you have to say is negative RVSM, they may give you a clearance to remain in RVSM airspace, or you may need to d
72 tdscanuck: I second zeke here...there's some subset of the aviation community that absolutely freaks out when you lose (or don't have) RVSM capability. ATC real
73 26point2: True. Not a big thing if planning to enter RVSM airspace. I used to resort to this tactic before RVSM certification was common too. But suppose one i
74 zeke: I have never had an issue with this, just let ATC know and they can sort it out. I have lost some of my air data before in RVSM airspace in a very 3r
75 Jetlagged: I know this, but the islands themselves are still small compared to the surrounding ocean and to the alternative of the landmass of the USA. You may
76 longhauler: This question arises from time to time. At my airline, pilots are issued iPads for use in the cockpit at all times. There are reasons why this is all
77 ha763: Someone in the comments finally posted the flight number and day that this turn back happened. Flight UA989 SFO-KOA on Aug 27. http://flightaware.com/
78 HAWK21M: Makes sense.....Its covering every corner of what could go wrong.......& avoid it. On the topic.....What is the SOP on carriage of Portable LED R
79 longhauler: It is listed in the "other PEDs with nil or negligible radio transmission capabilities" category, in that they can be used any time other than taxi,
80 KELPkid: Makes sense. Most LED flashlights operate on straight DC, and diodes aren't used as radio oscillators in any circuit I know of
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