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Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

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Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#61

Post by tajen »

aeternus wrote: post #44
Pyxl101 wrote: post #33

Earlier quoted context omitted.

How difficult is it to see what's happening on the ground at night from a plane? I've never been in a cockpit at night. I'd have to hope that taxiways are marked in some explicit way to make it clear that they're not runways, like with an X or some pattern of lights that's not on runways; or have all runways marked with an obvious pattern that indicates "land here" (so if you don't see that, you know you're not landi…

The numbers are not labeled in lights. Although this pic is blurry, this is SFO with both runways open: https://i.redd.it/hguxuyztxzdz.jpg The night of the accident, the left runway was closed and lights were turned off.. and they were expecting two runways and to land on the one on the right. There's still no excuse for this happening with two ATP-rated pilots that have done this type of landing thousands of times,…

But Harrison Ford’s senility (absent gaze, low liveliness) couldn’t even be hidden in his last Indiana Jones even though the camera crew can retake as many times necessary, I just wonder how he was still allowed to pilot.

Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#62

Post by powercf »

augustz wrote: post #45
nutcracker46 wrote: post #3

The report identifies good preventive measures. Autotuning the ILS would be handy, as would an aural alert for lateral deviation, perhaps announcing, "Localizer, Localizer." The crew may have caught the closure of 28L and planned better with a review of NOTAMS before top of descent and including them in the approach briefing. When I'm up there, and sleepy, I ask for a coffee and pull out the NOTAMS for one last look…

Just for SFO you have 84 NOTAMs. !SFO 06/079 SFO OBST RIG (ASN 2017-AWP-3368-NRA) 373740N1222224W (0.5NM NE SFO) 41FT (34FT AGL) FLAGGED AND LGTD 1806201400-1811010100 This is a flagged and lighted obstruction half a mile way that is 34 feet above ground level. Now put in a full route and takeoff airport and maybe if you have had some stops during the day. The NOTAM seems a bit long. Then if are overseas and have to…

Outputting that in lower case could be a small step to making them easier to parse, and therefore more likely to be read. I find the text you posted tiring even to look at.

THE REF (B) TURKISH NOTAM A3009/16 LTAAYNYX (111139 EUECYIYN JUL 2016) HAS NO GROUND, CANNOT PRODUCE ANY INTERNATIONALLY LEGAL EFFECT WITHIN ATHINAI FIR/ HELLAS UIR AND IS CONSIDERED NULL AND VOID.

vs

The ref (B) Turkish NOTAM A3009/16 LTAAYNYX (111139 Euecyiyn Jul 2016) has no ground, cannot produce any internationally legal effect within Athinai FIR/Hellas UIR and is considered null and void.

Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#63

Post by debt »

"The cues available to the flight crew to indicate that the airplane was aligned with a taxiway did not overcome the crew’s belief, as a result of expectation bias, that the taxiway was the intended landing runway."

Damn. It didn't matter that the whole world was telling him it was a taxiway because he was so sure it was a runway.

Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#64

Post by PhantomGremlin »

jonah wrote: post #20
wmblaettler wrote: post #11

Earlier quoted context omitted.

The very first thing I thought of upon reading your comment "The list of things tried so far to resolve the issue..." was "What about a big lighted 'x'?" then I clicked the link.

I'd like to know why they removed it.

Exactly my question. It's 9000+ feet long. Put a lighted red X on it every 1000 feet. Or, maybe Xes aren't the answer, but there must be some technique to produce a startling visual warning.

It's probably a situation like Chesterton's fence. There are probably good reasons for not having the Xes. At least I hope so, I hope it's not just "that costs money and then we have to maintain it". The money can't be an issue. How much would 500 or 1000 deaths cost? How expensive are all the other proposals which have been mentioned? Those aren't cheap either.

Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#65

Post by tialaramex »

cpitVoxRec wrote: post #27
tialaramex wrote: post #15

CVR overwrite is bad news here. The crew knew this was a serious problem when it happened, there's no way they should have allowed the CVR, crucial evidence of exactly what happened, to be overwritten. Perhaps the full report will have more detail on this, as it stands I have to believe somebody made the decision to overwrite this because they thought it'd be better if it didn't exist. Whether that's the crew, their…

They actually do clearly state in this PDF that a degree of fault lies in the crew being compromised by fatigue. Operating for 19 hours straight definitely places an individual in an area where one can be fighting to pay strict attention, even when it really counts. There's also plenty of communication with Air Traffic Control in the tower, and not a whole lot of gaps to introduce significant mystery, so it's pretty…

What I'd expect the CVR to provide good evidence of is the extent to which crew were actually doing the checks that should have caught this error, and their reaction when they belatedly discovered their true position.

Without even trying to mislead investigators a human will report a sanitised version of events when not cued by facts. "Then I scratched my arse and sniffed my finger" is not going to appear in this sanitised version of events even if true. Neither is "I glanced at the panel, I know I'm supposed to scan it, but usually anything important flashes red". The tower log helps, CVR is better, and CCTV better again.

It also really helps to get into the routine of analysing this stuff. If your aircrew routinely skip steps 4, 18 and 23 from the checklist, only finding that out when 200 passengers die in a crash is stupid. Let's find out now. That needs lots of heavy lifting, pilots have to trust the airlines not to fire them for ordinary human frailties, and airlines have to accept that their pilots are human and "But the manual says not to do that" doesn't make it stop happening magically.

You're right that fatigue is an obvious element here, and there are several technical countermeasures mentioned. I definitely don't want to come across as believing in a conspiracy to hide the facts, but on the other hand I struggle to believe that it took over 30 minutes to get this thing back down after the incident and so the overwrite was not a decision. And if we agree it was a decision, it was a seriously bad one that should not be repeated.

Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#66

Post by bdamm »

peterwwillis wrote: post #38
walrus01 wrote: post #28

Earlier quoted context omitted.

> I'm surprised that remote video cameras aren't used by tower controllers. There are software and hardware/network setups designed to do this now, in fact London City Airport is about to move to a fully virtual control tower, with a bunch of super high res pan/tilt/zoom cameras on a mast instead of an on-site tower. https://www.google.com/search?client=ubuntu&channel=fs&q=lon...

what happens when the camera lens gets a smudge?

These kinds of cameras usually live at the back of a tube that also serves as a sun shade and weather shelter.

Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#67

Post by bdamm »

joncrane wrote: post #57
SaberTail wrote: post #13

If anyone would like to listen to the ATC radio: https://www.youtube.com/watch?v=ZW-ETmZU0u8

OMG that is just pure gold! The United guy is SOOOO laconic. Like him speaking up on the open freq saved hundreds of lives and he sounds like he's reading yesterday's corn future prices.

This is the hallmark of a career professional pilot.

Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#68

Post by PhantomGremlin »

cpitVoxRec wrote: post #27
tialaramex wrote: post #15

CVR overwrite is bad news here. The crew knew this was a serious problem when it happened, there's no way they should have allowed the CVR, crucial evidence of exactly what happened, to be overwritten. Perhaps the full report will have more detail on this, as it stands I have to believe somebody made the decision to overwrite this because they thought it'd be better if it didn't exist. Whether that's the crew, their…

They actually do clearly state in this PDF that a degree of fault lies in the crew being compromised by fatigue. Operating for 19 hours straight definitely places an individual in an area where one can be fighting to pay strict attention, even when it really counts. There's also plenty of communication with Air Traffic Control in the tower, and not a whole lot of gaps to introduce significant mystery, so it's pretty…

Operating for 19 hours straight

Nobody was operating for that length of time. The captain had been awake for 19 hours, the first officer had been awake for 12 hours.

Granted, most people can't function anywhere near their peak performance after being awake for 19 hours. Also there's not enough information in the summary to know the captain's recent history; how much rest time did he have before that flight?

Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#69

Post by cmurf »

lolc wrote: post #36
cmurf wrote: post #5

I'm not operationally familiar with SFO. But based on experience at other airports, a taxiway at night can be a sea of black at even 100' above the ground. I would probably see airplane navigation lights at some point, but would I bet my life on it? No. So this incident has to be taken seriously. However, I'm still not clear from this reporting how the crew mistook blue taxiway lighting for white runway lighting. Thi…

Human consciousness tries to form a coherent model that integrates current sensory perception with knowledge. During an approach at night, scarce sensory input is interpolated to form a full model by the brain. The report uses the term "expectation bias" for this phenomenon. This drive for coherence runs below consciousness and we only notice when the coherence falls apart: When our sensory input cannot be reconciled…

I've never experience blue taxiway lights being confused as white/runway lighting, even in the very common case of uncontrolled airport where they frequently do leave taxiway lighting on, and runway lighting off, and use pilot controlled lighting to enable the runway lights on demand.

I'd expect at SFO, like any other major airport I have flown into, does have both runway and taxiway lighting enabled as pilots are on final approach. So they do have a reference: the white runway lights versus blue taxiway lights, which on final approach are in the same field of view. And even on the lowest intensity setting, runway lights are brighter than taxiway lights.

Something about this particular situation definitely is off. I don't know if there's something operationally different about SFO's lighting. Or if the pilots really were that fatigued, and this is a seriously underestimated factor.

Re: Abstract of the NTSB Report on Air Canada flight 759's taxiway overflight at SFO [pdf]

#70

Post by sandworm101 »

abaillargeon wrote: post #24

I've been anticipating the release of this report this since I heard about the incident. I work on an avionics product that's designed to prevent this exact scenario. We use the aircraft's position along with a database of runways and taxiways to determine if the aircraft is approaching the runway the pilot intends. If we determine the aircraft is landing, we issue a visual and aural alert to the pilot ("TAXIWAY LAND…

How do you account for winds and pressure differences, both of which will modify an approach. A plane may look like it is landing short, or to the left/right, when in fact the pilot is anticipating a change in wind as they drop in altitude.
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