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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

#41

Post by cyberferret »

FiloSottile wrote: post #23
rdtsc wrote: post #19

Earlier quoted context omitted.

This isn't quite a regular "runway incursion". That term is usually reserved for a taxiing aircraft (or maybe a service vehicle) which didn't stop in time at the threshold and went a bit beyond it. This is more like runway "confusion". A term I made up, not sure if there is such an official name for it.

Right, I meant that if pilots sort-of-routinely spot runway incursions, they surely won't land on 3 wide-body jets sitting there. This is why you want human pilots, instead of computers, not the opposite. A human can apply common sense and decide not to land on three planes after all even if it looks like a cleared runway.

> This is why you want human pilots, instead of computers

I actually believe the opposite is true. Systems like ACARS have managed to avoid the prevalence of air to air incidents that used to be almost an epidemic in the 60's and 70's.

Autolanding technology has brought planes home safely where a pilot would have had to go around and find an alternate aerodrome.

Re: SFO near miss might have triggered aviation disaster

#42

Post by hyperbovine »

FiloSottile wrote: post #4

I am just a passenger, but this looks very over-blown. A pilot aligned with the taxiway, that's bad. But no pilot would ever land on a runway (or taxiway) with 3 planes on it. Just search the Aviation Herald for "runway incursion". And indeed, he spotted them, communicated, went around. Aviation safety margins are so wide that this does not qualify as a near-miss.

> But no pilot would ever land on a runway (or taxiway) with 3 planes on it.

Just like no pilot would ever crash into the seawall short of 28L in broad daylight with unlimited visibility. In that case the pilots knew what was about to happen seconds before impact and they were powerless to stop it. I could easily see the same thing happening here. Airplanes are big cumbersome objects with a ton of inertia.

Re: SFO near miss might have triggered aviation disaster

#43

Post by desdiv »

charlietran wrote: post #3

There's an mp3 of the radio chatter here: https://forums.liveatc.net/atcaviation-audio-clips/7-july-ks... > Audio from the air traffic controller communication archived by a user on LiveATC.net and reviewed by this newspaper organization showed how a the confused Air Canada pilot asks if he’s clear to land on 28R because he sees lights on the runway. > “There’s no one on 28R but you,” the air controller responds. > A…

.

Re: SFO near miss might have triggered aviation disaster

#44

Post by chrisper »

dbroockman wrote: post #36
blhack wrote: post #34

People "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.

Seems like disaster was only avoided because there was good visibility. If there was fog that day, it sounds like this wouldn't have been avoided.

If there is fog you do not fly by hand. You use an automated landing system (ILS) in that case.

Re: SFO near miss might have triggered aviation disaster

#45

Post by cyberferret »

willidiots wrote: post #38
cyberferret wrote: post #33

Earlier quoted context omitted.

Because the pilot is almost never looking at a map on final approach. He is looking out the window, and in the dawn/dusk light, or with a setting sun in the background or inclement weather etc., a taxiway can look exactly like a runway. Don't forget that almost all taxiways run parallel to the runway, for about the same length. (NB: I used to be a commercial pilot.) In most airports I flew into, the surface material…

Seems like a design flaw. Do any taxiways have markings etc. to make them more distinguishable?

They do. They have different lighting systems/colours etc. to differentiate them.

Taxiways generally have green lights along the centerline to guide aircraft rolling on the ground, but runways usually have white (bright) lights along the edges. There are times when even THAT causes confusion, because sometimes the taxiway centreline lights can look like the edge lights of the runway - especially if the light is refracting off a wet windscreen.

So, in the end the problem is generally avoidable, but if you are on finals at a really busy airport after a gruelling 20 hours trans oceanic flight, at night, in the rain, and the tower is trying to hurry you up to expedite traffic, you can make mistakes.

Re: SFO near miss might have triggered aviation disaster

#46

Post by exDM69 »

FiloSottile wrote: post #4

I am just a passenger, but this looks very over-blown. A pilot aligned with the taxiway, that's bad. But no pilot would ever land on a runway (or taxiway) with 3 planes on it. Just search the Aviation Herald for "runway incursion". And indeed, he spotted them, communicated, went around. Aviation safety margins are so wide that this does not qualify as a near-miss.

Assuming the liveatc audio in the article has not been edited, it sounds like there's about 10 seconds between ATC giving go around and the United pilot saying they flew right over. With instructions given to Air Canada in between so it might have been seconds earlier.

Based on that, it was seconds away from a collision. It seems like a near miss when considering aviation safety margins.

Re: SFO near miss might have triggered aviation disaster

#47

Post by Animats »

Here's a night approach on 28R at SFO.[1] Same approach during the day.[2] The taxiway is on the right. It's a straight-in approach over the bay. The runway, like all runways at major airports worldwide, has the standardized lighting that makes it very distinctive at night, including the long line of lights out into the bay. This was in clear conditions. WTF? Looking forward to reading the investigation results.

The planes on the taxiway are facing incoming aircraft as they wait for the turn onto the runway and takeoff. So they saw the Air Canada plane coming right at them. That must have been scary.

[1] https://www.youtube.com/watch?v=rNMtMYUGjnQ [2] https://www.youtube.com/watch?v=mv7_lzFKCSM

Re: SFO near miss might have triggered aviation disaster

#48

Post by lisper »

FiloSottile wrote: post #4

I am just a passenger, but this looks very over-blown. A pilot aligned with the taxiway, that's bad. But no pilot would ever land on a runway (or taxiway) with 3 planes on it. Just search the Aviation Herald for "runway incursion". And indeed, he spotted them, communicated, went around. Aviation safety margins are so wide that this does not qualify as a near-miss.

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 did. Royally.

Re: SFO near miss might have triggered aviation disaster

#49

Post by kobeya »

FiloSottile wrote: post #4

I am just a passenger, but this looks very over-blown. A pilot aligned with the taxiway, that's bad. But no pilot would ever land on a runway (or taxiway) with 3 planes on it. Just search the Aviation Herald for "runway incursion". And indeed, he spotted them, communicated, went around. Aviation safety margins are so wide that this does not qualify as a near-miss.

What if the airport was fogged out and the Air Canada pilot was doing a instrument landing?

Re: SFO near miss might have triggered aviation disaster

#50

Post by rl3 »

FiloSottile wrote: post #4

I am just a passenger, but this looks very over-blown. A pilot aligned with the taxiway, that's bad. But no pilot would ever land on a runway (or taxiway) with 3 planes on it. Just search the Aviation Herald for "runway incursion". And indeed, he spotted them, communicated, went around. Aviation safety margins are so wide that this does not qualify as a near-miss.

https://en.wikipedia.org/wiki/USAir_Flight_1493

Though air traffic was not heavy at Los Angeles airport, the local controller was distracted as Flight 1493 was on final approach by a series of abnormalities, including an aircraft that inadvertently switched off the tower frequency and a misplaced flight progress strip, which resulted in the SkyWest flight being told to taxi into takeoff position while the USAir flight was landing on the same runway without the Metroliner ever being given a takeoff clearance.

Upon landing, the 737 collided with the twin-engine turboprop, continued down the runway with the turboprop crushed beneath it, exited the runway, and caught fire. All 12 people aboard the smaller plane were killed, as well as an eventual total of 23 out of the 89 passengers on the Boeing.

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