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NTSB Issues Investigative Update on San Francisco Airport Near Miss

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Re: NTSB Issues Investigative Update on San Francisco Airport Near Miss

#51

Post by jbg_ »

mseebach wrote: post #43
isomorphic wrote: post #27

Earlier quoted context omitted.

I don't think GPS is accurate enough for that sort of thing, you'd need ground radar, working with onboard computers that understand which runway you're cleared for, etc. (I'm not a pilot, I'm speculating.) If you read the Guardian article from planetjones' comment: https://www.theguardian.com/business/2017/aug/03/air-canada-... Quoting: The investigators said that as the Air Canada jet approached the taxiway just be…

It's called ILS, Instrument Landing System, and it's been around for literally 80 years. > The first landing of a scheduled U.S. passenger airliner using ILS was on January 26, 1938, when a Pennsylvania Central Airlines Boeing 247D flew from Washington, D.C., to Pittsburgh, Pennsylvania, and landed in a snowstorm using only the Instrument Landing System https://en.wikipedia.org/wiki/Instrument_landing_system Presumab…

ILS is separate from the radar system mentioned by parent. ILS uses directional radio signals from each end of the runway to provide a glideslope and lateral guidance, not radar.

The signals are transmitted from the ground and used for guidance by the aircraft. No part of ILS could alert ATC to anything since the ground stations are only transmitters.

Re: NTSB Issues Investigative Update on San Francisco Airport Near Miss

#53

Post by TrickyRick »

justinjlynn wrote: post #50
TrickyRick wrote: post #44

Earlier quoted context omitted.

Storage is cheap today, it wasn't 30 years ago when these rules were put in place (And probably some of the systems manufactured)

Retrofits to safety equipment are common when new issues are discovered. That said, an enforcement action or a procedure change is probably necessary in this case.

For sure, and it might get changed now, but it wouldn't surprise me if planes are still flying with age old cockpit voice recorders, simply because the requirements on that front haven't changed. (Bearing in mind this is just an educated guess, I have no idea about whether or not they have changed)

Re: NTSB Issues Investigative Update on San Francisco Airport Near Miss

#54

Post by andrewfree »

mseebach wrote: post #43
isomorphic wrote: post #27

Earlier quoted context omitted.

I don't think GPS is accurate enough for that sort of thing, you'd need ground radar, working with onboard computers that understand which runway you're cleared for, etc. (I'm not a pilot, I'm speculating.) If you read the Guardian article from planetjones' comment: https://www.theguardian.com/business/2017/aug/03/air-canada-... Quoting: The investigators said that as the Air Canada jet approached the taxiway just be…

It's called ILS, Instrument Landing System, and it's been around for literally 80 years. > The first landing of a scheduled U.S. passenger airliner using ILS was on January 26, 1938, when a Pennsylvania Central Airlines Boeing 247D flew from Washington, D.C., to Pittsburgh, Pennsylvania, and landed in a snowstorm using only the Instrument Landing System https://en.wikipedia.org/wiki/Instrument_landing_system Presumab…

They were sitting there because of a bomb threat at another airport and that was the only storage space. Did you read the article?

Re: NTSB Issues Investigative Update on San Francisco Airport Near Miss

#55

Post by mseebach »

jbg_ wrote: post #51
mseebach wrote: post #43

Earlier quoted context omitted.

It's called ILS, Instrument Landing System, and it's been around for literally 80 years. > The first landing of a scheduled U.S. passenger airliner using ILS was on January 26, 1938, when a Pennsylvania Central Airlines Boeing 247D flew from Washington, D.C., to Pittsburgh, Pennsylvania, and landed in a snowstorm using only the Instrument Landing System https://en.wikipedia.org/wiki/Instrument_landing_system Presumab…

ILS is separate from the radar system mentioned by parent. ILS uses directional radio signals from each end of the runway to provide a glideslope and lateral guidance, not radar. The signals are transmitted from the ground and used for guidance by the aircraft. No part of ILS could alert ATC to anything since the ground stations are only transmitters.

Yes, I know. But it's analogous to the GPS system the parents are discussing.

Re: NTSB Issues Investigative Update on San Francisco Airport Near Miss

#56

Post by mseebach »

andrewfree wrote: post #54
mseebach wrote: post #43

Earlier quoted context omitted.

It's called ILS, Instrument Landing System, and it's been around for literally 80 years. > The first landing of a scheduled U.S. passenger airliner using ILS was on January 26, 1938, when a Pennsylvania Central Airlines Boeing 247D flew from Washington, D.C., to Pittsburgh, Pennsylvania, and landed in a snowstorm using only the Instrument Landing System https://en.wikipedia.org/wiki/Instrument_landing_system Presumab…

They were sitting there because of a bomb threat at another airport and that was the only storage space. Did you read the article?

It's irrelevant why they were there, it's a taxi way, it's fine, indeed expected, for planes to hang out there. The important bit was why the AC tried to land there and the crew confirming their approach on ILS would have prevented that.

Re: NTSB Issues Investigative Update on San Francisco Airport Near Miss

#57

Post by TrickyRick »

probablybanned wrote: post #19

VASAviation made a video on this with radio traffic from the incident. https://www.youtube.com/watch?v=ZW-ETmZU0u8 (1:33)

That video doesn't match the sequence of events in the report (Which makes sense, it was published a few weeks ago). According to the report the remarks from UAL1 come as the airplane is overflying the taxiway.

Re: NTSB Issues Investigative Update on San Francisco Airport Near Miss

#58

Post by pmikesell »

notatoad wrote: post #23
modeless wrote: post #3

Before I couldn't imagine how anyone could make this mistake, but now I see it. The pilots were familiar with SFO and knew that there were two runways, but didn't realize the left hand runway lights were turned off, so they had an off-by-one error when choosing the runway.

i'm not a pilot and have no idea what it looks like when landing a plane at night, so i really shouldn't be commenting here, but: the report says the one operational runway had 2400 ft of approach lighting that was functional. The disabled runway had no approach lighting, and presumably the taxiway didn't have any approach lighting because nobody should be approaching a taxiway. So yes, they were just "off by one", b…

I a am a pilot. At night, after a long flight to a place you don't live at, you are desperately looking to orient yourself. They looked at the charts, saw 2 runways, and found them. It can be extremely disoritening, especially at a place like sfo where there are two parallel sets of runways.

What we need is better computer guidance. The tech is available, our legislature is not. Look at the incredible "taking out freedoms" pushback against adsb to see what I'm talking about.

Re: NTSB Issues Investigative Update on San Francisco Airport Near Miss

#59

Post by greenhouse_gas »

kpil wrote: post #36
matt_wulfeck wrote: post #28

Earlier quoted context omitted.

I'm wondering the same thing. Why don't planes land themselves at this point?

The main reason is that computers aren't very smart although I know that even some developers think that. Actually they can autoland but not everywhere and then you still need to tell them where, basically tune them in on the right glide path. Then you really need to be prepared to take over any second, which is a dangerous position on its own. (Just like all self driving cars right now.) It's still possible to selec…

>Actually they can autoland but not everywhere and then you still need to tell them where, basically tune them in on the right glide path.

Why can't the ATC or Pilot guide the computers to the right glidepath? And most importantly, if you're not going in that glidepath, you should get a major alarm, with ATC warned (so they can manually tell the pilot to abort).

Re: NTSB Issues Investigative Update on San Francisco Airport Near Miss

#60

Post by mosheroperandi »

TrickyRick wrote: post #52

The map view seems a bit off to me, UAL1 obviously saw the incoming plane and on the photos it looks to me like there are 4 planes in a straight line, yet UAL1 is oriented in the other direction on the radar.

I think it's the case as depicted in the first radar image, UAL1 turned 90-ish of degrees right on the exit from the taxi-way, and the other three lined up. It could be the angle of the camera is such that it's an illusion they're all in a straight line. That probably still gives them plenty enough view out the side of cockpit to see that the plane they're expecting is heading behind them and not in front of them where it should be.

I think the orientations in the subsequent screens where UAL-1 looks turned around are probably a case of the radar over-extrapolating from its heading from the turn and then not being able to tell its heading while it's parked.

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