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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]

#101

Post by DocTomoe »

oh_sigh wrote: post #97
organman91 wrote: post #9

As a private pilot, small planes going down occasionally are just a fact of life. But this incident scares me. There were four planes lined up on the taxiway the Air Canada narrowly missed. The worst aviation accident ever was a collision of two 747s resulting in 583 deaths: https://en.wikipedia.org/wiki/Tenerife_airport_disaster - this could have doubled that number.

Is it plausible that that AC759 could have taken out all 4 other planes? I don't really have a sense of the distances planes are spaced out on taxiways at major airports.

Spacing between planes on a taxiway is a lot shorter than you would imagine. Depending on type, a 25-50 meters apart is common.

Keep in mind that these four planes were preparing for take-off, meaning that they were fully fuelled...

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

#102

Post by DocTomoe »

powercf wrote: post #62
augustz wrote: post #45

Earlier quoted context omitted.

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 (1…

Yeah, good luck with changing hundreds of established, life-or-death-systems, most of them actually embedded in planes in the airline industry worldwide, at the same cutover date, to suddenly support mixed-case script.

Have a one-hour watch to understand what kind of beast you are wrestling here: https://media.ccc.de/v/31c3_-_6308_-_en_-_saal_1_-_201412281...

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

#103

Post by siberianbear »

joezydeco wrote: post #74
joncrane wrote: post #59

Earlier quoted context omitted.

I watched way more of that than I should have. It was way more interesting than I thought it would be. I would love to be an airline captain.

PilotsEyeTV is a really really neat thing. They sell entire box sets of whole flights. It's pretty cool that the European airlines allow this amount of camera work in the cockpit: http://pilotseye.tv/en/flightroutes/ If you really want to see something captivating, watch this clip of a Swiss A340 crew handling an overheating engine in-flight. It's incredibly well done. https://www.youtube.com/watch?v=rEf35NtlBLg

Wow, that Swiss A340 video was amazing. The pilots were just so chill. "Let's have some chocolate for the landing" LOL

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

#104

Post by everdev »

oh_sigh wrote: post #98
powercf wrote: post #62

Earlier quoted context omitted.

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 (1…

How much experience do you have reading all-caps text? It isn't necessarily a burden to people who are used to it, which all airline pilots are.

I'm sure prior experience is a big factor, but I could see how the greater height variances in lower case text can make it easier to read.

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

#105

Post by stordoff »

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.

Reminds me of the BA Flight 9 announcement:

> Ladies and gentlemen, this is your captain speaking. We have a small problem. All four engines have stopped. We are doing our damnedest to get them going again. I trust you are not in too much distress.

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

#106

Post by donavanm »

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…

As others pointed out there are fundamental problems with the system and usability of NOTAMs. Its a little absurd that theyre always used to blame the operator (“should have read the NOTAM”) when a flight briefing might have 10s or 100s applicable ones and a VAST number are junk. It reeks of retrospective blame seeking.

That said there is some traction around this. And some interesting alternative takes (https://opsfox.net), which have their own problems.

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

#107

Post by hueving »

mortenjorck wrote: post #43
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…

The recommendations look like important steps, especially the concept of a system that alerts pilots to runway surface non-alignment. I have to wonder, though, does it always take a close call like this (or worse) to bring up such a proposal? Does the NTSB also study otherwise safe flights to identify risks in pilot, tower, or ground crew human factors and make proactive recommendations?

>does it always take a close call like this (or worse) to bring up such a proposal?

At this point yes. There is a saying that "FAA regulations are written in blood" as a result.

It seems conservative on the surface but at this point the current system is incredibly safe and making changes without clear huge upsides isn't worth the risk of unintended consequences.

Pilot attention is at a premium during landing. The computer shouting "localizer" at you during an approach because you're misaligned might be the straw that breaks the cognitive burden's back while you're trying to deal with another crisis.

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

#108

Post by lolc »

cmurf wrote: post #69
lolc wrote: post #36

Earlier quoted context omitted.

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…

They expected to see two lit runways. They saw two lit lanes and their tired and distracted brain did the rest.

Obviously it's a rare occurrence otherwise airport lighting would have been adjusted to avoid the mistake.

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

#109

Post by Arn_Thor »

oh_sigh wrote: post #97
organman91 wrote: post #9

As a private pilot, small planes going down occasionally are just a fact of life. But this incident scares me. There were four planes lined up on the taxiway the Air Canada narrowly missed. The worst aviation accident ever was a collision of two 747s resulting in 583 deaths: https://en.wikipedia.org/wiki/Tenerife_airport_disaster - this could have doubled that number.

Is it plausible that that AC759 could have taken out all 4 other planes? I don't really have a sense of the distances planes are spaced out on taxiways at major airports.

The KLM which had barely reached minimum takeoff speed and started to take off still flew 150 meters after it had plowed through the upper half of the PanAm and lost an engine and the main wheels. There's a lot of momentum in a moving plane, and they're stacked very close when holding on the taxiway

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

#110

Post by Arn_Thor »

djrogers wrote: post #85
TylerE wrote: post #41

Earlier quoted context omitted.

I'd assume like cameras used at sporting events the lens would be covered by a clear plastic film on a roll, which can be moved to get a clean section. A bit like those toilet seat covers in airports, ironically.

> covered by a clear plastic film on a roll, which can be moved to get a clean section. A bit like those toilet seat covers What? Is that really a thing? Toilet seat covers on a roll? How would that even work?

real as you and me https://youtu.be/Lfrhgh6ZlQI
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