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SFO near miss might have triggered aviation disaster

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Re: SFO near miss might have triggered aviation disaster

#311

Post by [deleted] »

wfunction wrote: post #260
throwanem wrote: post #248

Earlier quoted context omitted.

Automatic landing systems rely on ground support by way of microwave signals from transmitters installed near autoland-capable runways. There's no general position information, and the airborne part of the system can't operate independently of the part on the ground. Civilian GPS signals are limited in terms of position accuracy, too. I believe the CEP is ten meters. That's not bad, but it's not good enough to land a…

Thanks for the detailed response. > Automatic landing systems rely on ground support by way of microwave signals from transmitters installed near autoland-capable runways. There's no general position information, and the airborne part of the system can't operate independently of the part on the ground. Yes, I understand the landing portion has other kinds of support. However, I don't understand how it can not have th…

[deleted]

Re: SFO near miss might have triggered aviation disaster

#312

Post by FeepingCreature »

ryandrake wrote: post #60
wfunction wrote: post #40

Earlier quoted context omitted.

Thank you! That raises the question, (a) why is there no kind of warning system for when you're about to land on the wrong runway (there's a GPS system in the aircraft that knows where you're going, right?) and (b) why is the pilot (or at least co-pilot) never looking at a map on final approach? Is it really that dangerous for anyone to take a quick glance?

When flying visually (VFR), taxiway lighting and runway lighting are visually very different. Taxiway lighting is almost always blue, whereas runway lighting is white (with any displaced threshold marked with red lights). In daylight, the markings on the runway are unmistakably different. I'm not instrument rated but my understanding is that with ILS, instrument approaches can handle multiple parallel runways precise…

With all due respect, blue and white seem like terrible colors to pick if they are supposed to be clearly distinguishable.

Re: SFO near miss might have triggered aviation disaster

#313

Post by mirimir »

Piskvorrr wrote: post #277
amelius wrote: post #217

Earlier quoted context omitted.

When the GPS in my car shows two lanes, it clearly marks whether I should take the left or right one.

...but it sometimes detects your position as being in the other lane than where you actually are (or even a block away).

That can get especially crazy during construction, and after new roads open.

Re: SFO near miss might have triggered aviation disaster

#315

Post by floatingatoll »

RX14 wrote: post #163
PhasmaFelis wrote: post #108

Earlier quoted context omitted.

I'd imagine, as well, that a transmitter powerful enough to drown out a control tower would be very, very difficult to conceal.

I think you'd be very surprised what a lot of power and a shit antenna can do. Obviously won't last when someone comes along with DF equipment, but it really wouldn't be hard to conceal visually.

Visually is the key word here. RF-wise, you may as well put a beacon on the moon and scream "LOOK AT ME" for all the good it'll do when the very, very angry FAA/FCC vans show up.

Re: SFO near miss might have triggered aviation disaster

#316

Post by deelowe »

briandear wrote: post #239
gambiting wrote: post #235

Earlier quoted context omitted.

Stupid question - can you be certified as a commercial pilot if you are colourblind?

You can’t even be certificated as a Private Pilot if you are colorblind.

Why do people comment on things they know nothing about? Of course you can.

Re: SFO near miss might have triggered aviation disaster

#317

Post by Tloewald »

athenot wrote: post #302
kbutler wrote: post #291

Earlier quoted context omitted.

Someday, perhaps computer programmers will start applying this principle.

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 being smooth and frictionless. (See Don Norman's classic example of fire escapes that send people into basements to be trapped.)

Re: SFO near miss might have triggered aviation disaster

#318

Post by mikeash »

I wonder just how likely this was to end in disaster. It feels overstated. The pilot in question seemed to think something was wrong, he just hadn't figured it out yet. I imagine he would have seen the aircraft on the taxiway in time to go around on his own if he hadn't been warned off.

I'm having trouble figuring out the timeline. The recording in the article makes it sound like this all happened in a matter of seconds, but it's edited down to the highlights so that's misleading. LiveATC has an archived recording of the event (http://archive-server.liveatc.net/ksfo/KSFO-Twr2-Jul-08-2017..., relevant part starts at about 14:45) but even those appear to have silent parts edited out. (That recording covers a 30 minute period but is only about 18 minutes long.) In the archived recording, about 40 seconds elapse between the plane being told to go around and the "flew directly over us" call, but I don't know how much silence was edited out in between.

Certainly this shouldn't have happened, but I wonder just how bad it actually was.

Re: SFO near miss might have triggered aviation disaster

#319

Post by lttlrck »

goblin89 wrote: post #299
kbutler wrote: post #291

Earlier quoted context omitted.

Someday, perhaps computer programmers will start applying this principle.

Perhaps not all tech companies care to push past human error in each postmortem (or even have a proper formal process at all), but some are known to do just that. Etsy and Google are among the well-documented cases. > This idea of digging deeper into the circumstance and environment that an engineer found themselves in is called looking for the “Second Story”. In Post-Mortem meetings, we want to find Second Stories t…

This was address very well by a video posted on the Piper Alpha story yesterday.

https://news.ycombinator.com/item?id=14732404

https://www.youtube.com/watch?v=S9h8MKG88_U

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