Earlier quoted context omitted.
"...including the installation of an unlit, nonreflective elevated lighted X at the threshold of taxiway Tango..." Unlit lighted X. Right.
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SFO near miss might have triggered aviation disaster
361–370 of 435 posts
Re: SFO near miss might have triggered aviation disaster
#362Earlier quoted context omitted.
I'm a private pilot who has flown into SFO once, and flies over SFO on a regular basis (I'm based at Palo Alto airport). This is not being overblown. If you listen to the audio tape, the tower orders the go-around at the 33 second mark, and United 1 reports that "Air Canada flew directly over us" 16 seconds later. That is a breathtakingly close call. Safety margins are wide when pilots don't screw up. But this one di…
The recording is edited for highlights. The LiveATC archive has a ~40 second interval between "go around" and "flew directly over us" and even that archive is edited to remove silence, so the real interval may have been even longer.
Can you post/link the unedited version? I can't find it.
Notwithstanding the timing on the tape, the AC jet could not have been very far away because the fact that he was lined up with the taxiway was first noted by a plane on the ground. That would not have been evident unless the plane was very close.
Re: SFO near miss might have triggered aviation disaster
#363Possible explanation for why this happened: it was night, and the parallel runway 28L was closed and therefore unlit. The pilot may have mistaken 28R for 28L and hence the taxiway for 28R. This comes nowhere near excusing this mistake (there is no excuse for a screwup of this magnitude) but it makes it a little more understandable.
Re: SFO near miss might have triggered aviation disaster
#364Near as I can tell HIRL could not have been on, they were not following another aicraft to land, and the runway and taxiway lighting must've been sufficiently low that the taxi lights (low intensity version of a landing light) on the queued up airplanes on the taxiway, made it look like the taxiway was the runway. Pilot fatigue, and experience at this airport also are questions.
http://flightaware.com/resources/airport/SFO/IAP/ILS+RWY+28R...
All runways have high intensity runway lighting (HIRL) and 28R has touchdown zone and centerline lighting (TDZ/CL). Runway lights are white, taxiway lights are blue. If you see these elements, there's no way to get confused. So my assumption is the pilots, neither of them, saw this distinction.
HIRL is typically off for visual landings even at night. That's questionable because night conditions are reduced visibility situations and in many other countries night flying is considered as operating under instrument rules, but not in the U.S. You do not need instrument rated aircraft or pilot certification. For a long time I've though low intensity HIRL should be enabled briefy in the case of visual night landings, where an aircraft is not following behind another, at the time "runway in sight" verbal verification happens between ATC and pilot.
Re: SFO near miss might have triggered aviation disaster
#365Earlier quoted context omitted.
The absolutely stellar safety record of the airline industry exists because they have repeatedly and consistent pushed past human error as an explanation for a crash. Understanding that if a human made this mistake, another future human will likely make the exact same mistake, they push to understand _why_ an airline captain that should know made this error. Then try to correct for that. If every crash was written of…
Someday, perhaps computer programmers will start applying this principle.
While I agree generally with that sentiment, there's a key difference.
Airplane pilots are licensed, certified, trained, and regulated. There's a clear floor to who is allowed in the cockpit (barring extreme emergencies, e.g., incapacitation of a pilot).
By contrast, software is made available to pretty much the entire world. And it turns out that two thirds of all adults have "poor", "below poor", or no computer skills at all. Which is to say, the qualifications floor is nonexistent.
If you're designing a one-size-fits-all system, you've got to design for this. The results, I'd argue, are ... not particularly satisfactory.
I'm not saying "don't design for the user in mind", or "don't dismiss user error". But rather, than when your floor is zero, you're going to have a remarkably difficult challenge.
https://www.reddit.com/r/dredmorbius/comments/69wk8y/the_tyr...
Re: SFO near miss might have triggered aviation disaster
#366Earlier quoted context omitted.
They do. That's what UX is all about. Not just UI, not just making thing possible or visual, but actually making the experience as smooth and frictionless as possible.
UX is the bane of usability (at least as practiced). E.g. We've had professional "UX" designers seriously contend that "cancel" buttons should be made to not look like buttons. The joke at a certain large company was that if the UX designers had their way every default button would be big and green and every other button would be invisible. True usability is about helping people make the correct decision, not just be…
I'm a daily user of some of the most complicated engineering software on the market. Every single release promises "Easier to use!" but all they do is make the most basic beginner-level actions more prominent and hide all medium to advanced level important functionality behind 3 extra clicks.
The end result is a beginner can do a tutorial exercise in 20 minutes instead of 30, while any true day to day work in the software takes 4 hours instead of 2.
Re: SFO near miss might have triggered aviation disaster
#367Earlier quoted context omitted.
It feels like it could be solved incredibly easily by a row of lights at the beginning/end of both the taxiway and the runway, bright red for taxiway, bright green for the runway. If you are attempting to land on the strip marked red, then you are doing something wrong. In case that the taxiway is legitimately used for landing, change the colours around. I guess it hasn't been done for "reasons", I'd be quite interes…
It is done pretty much like that. PDF warning, page 31: https://www.faa.gov/airports/southern/airport_safety/part139... Taxiways are marked with blue lights. Here's a video of a night landing on the same runway, the approach lighting is unmistakable: https://www.youtube.com/watch?v=rNMtMYUGjnQ
Yeah. At 1:18 that's clearly HIRL enabled. There's no ambiguity that's for a runway rather than taxiway. And it's not possible to visually misalign yourself with the taxiway, the whole point of HIRL is a visual aid for precision instrument landings in bad weather for Cat I and II ILS landings. On an instrument landing, it's not legal to go below decision height (200 and 100 feet respectively) unless you meet the visual reference requirement in 91.175 c3, ergo the HIRL lighting is simply unambiguous for a night VFR landing, and makes me wonder if it was even on.
Re: SFO near miss might have triggered aviation disaster
#368People "could" run their cars off of bridges every day, but they don't because they can see, and because roads have signs warning them of curves. This sounds like a story of how well the aviation system works more than anything. The pilot is in constant communication with the tower. The system worked as intended here and he went around. It seems like a non story.
Comment like that would put me off hiring you for any sort of mission- or safety-critical project. The approach for Asiana 214 looked fine until it wasn't; that was less than 4 years ago. Maybe you should stare at the video of that crash for a while and consider the large consequences that can ensue from a small error of judgement made a little too late.
One of my hobbies is shooting fire effects at big music festivals. We're shooting huge flames in front of 10s of thousands of people. I think that is pretty safety-critical.
We have a very rigid communication protocol that I designed based on my experience as a pilot and all the time I've spent flying with my father, who is a very experienced pilot.
The communication protocol and operational checklists are there specifically to catch human errors.
For instance: "snoop" (which is a sort of soapy water used for checking gas lines for leaks) every gas line any time it is changed. Snooping something, finding a leak, and then either reseating the gas fitting or shutting off its supply is the system working properly.
You could absolutely write an article that said "multiple gas leaks found on fire effects system", omitting the part where they were immediately found and fixed as part of the operation of the system.
I also wrote the ignition and control systems for a fire effect that we use, which has fail-safes built into every stage of its operation. That doesn't mean that failure modes don't ever occur (for instance: dead battery on the controller, out of range events, etc), it means that I designed around them so that they occur safely.
So I'm sorry that you wouldn't hire me for safety-critical systems. I'm curious what safety critical system you design or manage, because the idea that you either don't think errors will ever occur, or don't know what they are and how to design around them, is perplexing.
Re: SFO near miss might have triggered aviation disaster
#369Earlier quoted context omitted.
this sounds like the start of a good idea, but we should choose something that works for colorblind people and red/green colorblind people too.
Stupid question - can you be certified as a commercial pilot if you are colourblind?
Yes, but the certificate comes with a limitation (color signal landing daytime only proscription; or night and color signal landing proscription).
The requirements vary depending on class of medical certificate but in this context it's a class I medical for airline transport pilots (not commercial pilots) so it's complicated.
Also, full on dichromats or monochromats are rare. Usually people are one of three anomalous trichomats. Hence testing is required to determine if it's a problem. The initial test is designed to have a high failure rate, and the exception tests to get the restrictions lifted take more effort.
https://www.aopa.org/go-fly/medical-resources/health-conditi...
Re: SFO near miss might have triggered aviation disaster
#370Earlier quoted context omitted.
It is a very Silicon Valley thing to assume that everyone else is an idiot and needs to be disrupted, with not a thought given as to why things are the way they are. Sort of funny to watch it from the side I assure you that there is a reason AM is used. The reason is that in the case that two stations are transmitting, everyone will be aware of it and the stronger signal may be heard. This is not something that FM ca…
Digital only require better signal if you want high data rates. With analog signal the human has to do the error correction, i.e. extract the signal from the snowy picture. Digital signals can use error correcting codes to get the same result. The more bits you have for error correction, the better your recovery can be.
With a lot of FEC, you can sort of approach it, but still not quite. Human brain is a lot better at picking out voice out of noise than any algorithm currently known. That is , for example, why your Alexa cannot take your commands in the middle of a 100-person party, but your interlocutor can hear you and respond.