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A Lufthansa A350's frustrating Oakland diversion

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Re: A Lufthansa A350's frustrating Oakland diversion

#81

Post by Analemma_ »

mjevans wrote: post #65
noxvilleza wrote: post #17

Earlier quoted context omitted.

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…

I'm surprised a computer assisted landing sequence can't _increase_ the rate of landed planes, though I assume doing so would require subordinating all the inbound aircraft to the local traffic control system.

The problem with having computer separation be less than pilot separation is, what happens if the computers fail and the pilots have to take over? Then they're suddenly in a situation where they're already below whatever the minimum safe pilot separation is, and now you've potentially turned a recoverable failure into an unrecoverable one. If the whole point of having pilots is to be backups for the computers, the computer situation has to have more margin than the equivalent pilot one, even if efficiency is being left on the table.

(The only way around this is to not have pilots as backup, and turn the whole thing over to the computers, but we're not ready or willing to take that step yet)

Re: A Lufthansa A350's frustrating Oakland diversion

#82

Post by bilbo0s »

KennyBlanken wrote: post #61
Hansenq wrote: post #29

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 du…

You're leaving out that they had a filed flight plan which for an international flight means controllers had many hours of notice as to when the flight was scheduled to arrive and that they would be looking for an ILS approach and it was the responsibility of approach controllers to have a spot in the pattern for them. They arrived in the area on time, and controllers had not allocated it a spot, which is why the pil…

They arrived in the area on time

Huh?

They arrived way outside their window. I realize they also left MUC late, but still.

Re: A Lufthansa A350's frustrating Oakland diversion

#83

Post by jcrawfordor »

michael_j_x wrote: post #55
CaliforniaKarl wrote: post #50

Earlier quoted context omitted.

If you mean “traffic pattern” (from https://www.faa.gov/air_traffic/publications/media/pcg_10-12... ), that is also something you would do visually, which I don’t think Lufthansa would accept. As for not being able to give an accurate estimate, that is not for the on-the-radio approach controller to calculate, given their view of the airspace. The video posted by parent shows how long the inbound flows were (at least…

I meant for the ATC to provide a descent estimate of when Lufthansa should be expected to enter the AERODROME TRAFFIC CIRCUIT (since you want tolink the FAA glossary) in order to land (they had them on a hold pattern for 35+ minutes). This is independent of whether the approach is IFR or VFR. A TOWER controller has all the information necessary to calculate that estimate, and should be expected to do so, the same way…

Most of the queue would have been with approach, not tower. The aircraft sequenced to land were split across at least two controllers, tower and approach, and possibly more than one approach controller depending on how SFO splits them up. I would expect approach to be able to provide a reasonable estimate but it seems like in this case the estimate was found to be four minutes off, which seems totally within the bounds of a reasonable estimate from an approach controller.

The traffic pattern (US term) isn't really a factor here either way, airliners flying visual still usually use charted routes (like the instrument procedures) or radar vectors rather than the pattern. Remember that the pattern is only about one mile out from the field. By the time airliners are that close they're probably cleared.

Re: A Lufthansa A350's frustrating Oakland diversion

#84

Post by [deleted] »

xenadu02 wrote: post #46
noxvilleza wrote: post #37

Earlier quoted context omitted.

> that nobody else does it. Apparently some Canadian carriers do also have this as a SOP. Around the time this happened I spoke to some friends who are ATCs (in the US) who all immediately agreed it was a very reasonable request, especially given that the request was made far enough out (so it wasn't like they'd have to quickly scramble to respace the incoming planes correctly in the sequence).

Because Lufthansa left a few hours late they arrived during a super busy arrival window. AFAIK ATC had nearly 30 planes already in the queue for landing with spacing for visual. To get Lufthansa in any sooner they'd need to send updated instructions to a lot of planes to make a gap. If Lufthansa had arrived two hours earlier or later it wouldn't have been an issue. Indeed they were able to depart OAK around two hours…

[deleted]

Re: A Lufthansa A350's frustrating Oakland diversion

#85

Post by p3n1s »

michael_j_x wrote: post #55
CaliforniaKarl wrote: post #50

Earlier quoted context omitted.

If you mean “traffic pattern” (from https://www.faa.gov/air_traffic/publications/media/pcg_10-12... ), that is also something you would do visually, which I don’t think Lufthansa would accept. As for not being able to give an accurate estimate, that is not for the on-the-radio approach controller to calculate, given their view of the airspace. The video posted by parent shows how long the inbound flows were (at least…

I meant for the ATC to provide a descent estimate of when Lufthansa should be expected to enter the AERODROME TRAFFIC CIRCUIT (since you want tolink the FAA glossary) in order to land (they had them on a hold pattern for 35+ minutes). This is independent of whether the approach is IFR or VFR. A TOWER controller has all the information necessary to calculate that estimate, and should be expected to do so, the same way…

Aerodrome traffic circuit is the ICAO term for traffic pattern, which is it what it is called in the US (it may be in the glossary but the point is that manual uses "traffic pattern" repeatedly). And this "traffic circuit" you refer to is almost always a VFR thing, as IFR approaches use specific charted procedures that generally do not end with a traffic circuit.

https://skybrary.aero/articles/aerodrome-traffic-circuit

Re: A Lufthansa A350's frustrating Oakland diversion

#86

Post by trentnelson »

KennyBlanken wrote: post #61
Hansenq wrote: post #29

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 du…

You're leaving out that they had a filed flight plan which for an international flight means controllers had many hours of notice as to when the flight was scheduled to arrive and that they would be looking for an ILS approach and it was the responsibility of approach controllers to have a spot in the pattern for them. They arrived in the area on time, and controllers had not allocated it a spot, which is why the pil…

ATC works on a first come, first served basis. (Unless you’re Air Force 1/2, or a survival flight, or declare an emergency.)

So just being in the system hours beforehand doesn’t really mean much. ATC don’t plan ahead based on what’s in the system, per se.

Re: A Lufthansa A350's frustrating Oakland diversion

#87

Post by shkkmo »

MBCook wrote: post #76
KennyBlanken wrote: post #61

Earlier quoted context omitted.

You're leaving out that they had a filed flight plan which for an international flight means controllers had many hours of notice as to when the flight was scheduled to arrive and that they would be looking for an ILS approach and it was the responsibility of approach controllers to have a spot in the pattern for them. They arrived in the area on time, and controllers had not allocated it a spot, which is why the pil…

Arrived on time? They left hours late from the departing airport.

Flight plans get updated when plans are delayed on takeoff. SFO should have had the arrival time from the updated flight plan for quite a while.

Re: A Lufthansa A350's frustrating Oakland diversion

#88

Post by jcrawfordor »

KennyBlanken wrote: post #61
Hansenq wrote: post #29

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 du…

You're leaving out that they had a filed flight plan which for an international flight means controllers had many hours of notice as to when the flight was scheduled to arrive and that they would be looking for an ILS approach and it was the responsibility of approach controllers to have a spot in the pattern for them. They arrived in the area on time, and controllers had not allocated it a spot, which is why the pil…

The flight plan factors into flow timing, which is used to manage capacity, but there's no reservation of a landing time. Flight plan timings aren't accurate enough for that to be feasible when you have landings at close to one a minute.

The flow timing rate used for approaches to SFO during visual conditions is based on visual approaches, so this particular aircraft didn't fall into the expectations used for that planning mechanism. Even then it's not a forward looking plan, just a rate limit on arrivals that causes departure clearances to be delayed. I'm not even sure if it works for international flights.

Re: A Lufthansa A350's frustrating Oakland diversion

#89

Post by koyote »

YeBanKo wrote: post #30

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 appro…

There's also this crash that happened while ILS was broken: https://en.wikipedia.org/wiki/Asiana_Airlines_Flight_214

This was ultimately pilot error but also due to the fact that the pilots were not as accustomed to doing visual landings.

Re: A Lufthansa A350's frustrating Oakland diversion

#90

Post by lxgr »

MBCook wrote: post #76
KennyBlanken wrote: post #61

Earlier quoted context omitted.

You're leaving out that they had a filed flight plan which for an international flight means controllers had many hours of notice as to when the flight was scheduled to arrive and that they would be looking for an ILS approach and it was the responsibility of approach controllers to have a spot in the pattern for them. They arrived in the area on time, and controllers had not allocated it a spot, which is why the pil…

Arrived on time? They left hours late from the departing airport.

I wonder if there is any mechanism that reconfirms landing slots (and other aspects of the flight plan) still being available after a delayed takeoff for cases like this.

Is it really just a matter of taking off and hoping for the best, or did somebody in the chain of granting a take-off clearance miss something?

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