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A Lufthansa A350's frustrating Oakland diversion

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Re: A Lufthansa A350's frustrating Oakland diversion

#21

Post by kayodelycaon »

jMyles wrote: post #18
riversflow wrote: post #8

I see this as a reap what you sow moment for Lufthasa. Why should ATC at a busy airport be so accommodating? Lufthasa is the one making this hard on everyone. I used to watch both these airports fairly frequently from Oyster bay regional park, they are both super busy with flights often lining up to the horizon.

> Why should ATC at a busy airport be so accommodating? Is it really so much to ask that an ILS-equipped airport... provide an ILS approach? I'm generally on your side here; the controllers did a good job with what resources they had. But there seem to be an awful lot of oddities / operational hangups through NorCal TRACON.

ILS approaches require far more separation than visual ones.

Re: A Lufthansa A350's frustrating Oakland diversion

#23

Post by jaywalk »

noxvilleza wrote: post #17
riversflow wrote: post #8

I see this as a reap what you sow moment for Lufthasa. Why should ATC at a busy airport be so accommodating? Lufthasa is the one making this hard on everyone. I used to watch both these airports fairly frequently from Oyster bay regional park, they are both super busy with flights often lining up to the horizon.

This wasn't some new policy of Lufthansa though, apparently it's their SOP for basically all airports. Outside the US, I'm not sure if visual approaches are all that common for (heavy) aircraft at night. Overall, the reason that SFO wants visual approaches is to increase rate of landing, and the reason that Lufthansa wants ILS is to increase safety -- your phrasing "Lufthasa is the one making this hard on everyone" j…

> your phrasing "Lufthasa is the one making this hard on everyone" just seems wrong, having more safety seems totally justified and reasonable here.

It's so "justified and reasonable" that nobody else does it. Maybe it's not quite so justified or as reasonable as you think.

Re: A Lufthansa A350's frustrating Oakland diversion

#24

Post by kayodelycaon »

jMyles wrote: post #22

The bigger issue here is that the ILS is being set aside in favor of visual approaches in order to slot in a few more approaches per hour. What's the point of equipping SFO with ILS if it's just going to sit idle?

ILS is needed when conditions don’t allow visual approaches. Like, clouds existing.

Re: A Lufthansa A350's frustrating Oakland diversion

#25

Post by jaywalk »

jMyles wrote: post #18
riversflow wrote: post #8

I see this as a reap what you sow moment for Lufthasa. Why should ATC at a busy airport be so accommodating? Lufthasa is the one making this hard on everyone. I used to watch both these airports fairly frequently from Oyster bay regional park, they are both super busy with flights often lining up to the horizon.

> Why should ATC at a busy airport be so accommodating? Is it really so much to ask that an ILS-equipped airport... provide an ILS approach? I'm generally on your side here; the controllers did a good job with what resources they had. But there seem to be an awful lot of oddities / operational hangups through NorCal TRACON.

With every other plane on visual, they can't just stick an ILS approach in there without messing everyone else up.

Re: A Lufthansa A350's frustrating Oakland diversion

#26

Post by wtallis »

kayodelycaon wrote: post #19
wtallis wrote: post #11

Earlier quoted context omitted.

Yeah, whether Lufthansa's polices are reasonable or excessively cautious is debatable, but the ATC here obviously gave unambiguously wrong information about the delay.

Delays are estimates. They can’t be guaranteed. All it takes is one other plane to be slow to act.

Estimates and predictions that turn out to be wrong are still wrong.

And when the estimate was wrong by 50% and counting, and the ATC wasn't offering any information other than another dubious estimate, and the ATC was not handling the flights in a FIFO order, the Lufthansa pilots were left with uncomfortably little useful information about their situation.

Re: A Lufthansa A350's frustrating Oakland diversion

#27

Post by daedalus_f »

Like in the youtube video's comments section, I suspect everyone on HN is going to assume that the ATC was simply being petty, and perhaps that was the case. But...

We don't know what the approach into SFO looked like that night, but you can bet it was busy. VASAviation videos are often highly misleading in this regard. Most of the talk on the ATC frequency is cut (sometimes explicitly, sometimes not) leaving just that relevant to the videos content, the time is compressed and they only plot a few of the planes involved, making the airspace look clear.

My understanding is that SFO often has two closely spaced parallel runways taking arrivals. The visual approach is preferred because then the pilots on parallel approaches keep visual separation from each other, allowing more frequent landings. An ILS approach requires more space between planes (because ATC remains responsible for separation). Hence, the Lufthansa had to wait for a gap big enough to fit that ILS approach in, or the whole stack of planes lined up for the approach would have to be juggled - how feasible that would be I don't know.

Re: A Lufthansa A350's frustrating Oakland diversion

#28

Post by jaywalk »

kayodelycaon wrote: post #24
jMyles wrote: post #22

The bigger issue here is that the ILS is being set aside in favor of visual approaches in order to slot in a few more approaches per hour. What's the point of equipping SFO with ILS if it's just going to sit idle?

ILS is needed when conditions don’t allow visual approaches. Like, clouds existing.

Clouds at SFO???? Never!

Re: A Lufthansa A350's frustrating Oakland diversion

#29

Post by Hansenq »

There's a follow up video to the one linked in the story that provides a lot more context missing in this piece. https://www.youtube.com/watch?v=4zHxdn8oz20

Basically, SFO normally does VFR parallel approaches at night. Approach sequences these approaches miles beforehand, so there can be a chain of 10-20 aircraft all sequenced to land before responsibility is even transferred to SFO's tower. The incident happened during a particularly busy landing time at SFO, so there was indeed a massive chain of aircraft coming in to land.

Lufthansa was the only aircraft asking for ILS. Because ILS needs greater separation, that would require breaking the chain of approaches, sequencing a single ILS approach, then resuming. The chain of landings already sequenced takes priority, so Lufthansa would have to wait 30+ minutes for a gap to appear. By the time that gap appeared, Lufthansa had just decided to divert to Oakland. If Lufthansa had arrived a bit earlier or a bit later, they would have been sequenced just fine.

ATC could have been a bit more accommodating in rerouting their divert to SFO as soon as the a gap appeared, but Lufthansa was also the only airline requesting ILS, and they're already dealing with sequencing 20+ aircraft during a busy time. It's not clear who's in the wrong here; just an unintended consequence from many well-intentioned decisions.

Re: A Lufthansa A350's frustrating Oakland diversion

#30

Post by YeBanKo »

Maybe the reason why Lufthansa does not allow visual approach at SFO at night, could be after the Air Canada near miss.

> The NTSB determined the probable cause was the Air Canada flight crew's confusion of the runway with the parallel taxiway, with contributing causes including the crew's failure to use the instrument landing system (ILS), as well as pilot fatigue.

FAA changed the rules for SFO and made visual approaches forbidden at night "when an adjacent parallel runway is closed" [2]. Maybe Lufthansa plays it safe and requires ILS for all long haul night landings.

[1] https://en.wikipedia.org/wiki/Air_Canada_Flight_759

[2] https://www.flightglobal.com/faa-changes-san-francisco-landi...

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