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A Lufthansa A350's frustrating Oakland diversion

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Re: A Lufthansa A350's frustrating Oakland diversion

#111

Post by lainga »

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…

What's the rationale? Maybe the jetstream reverses and the 2-hour delay leaving MUC gets erased during flight?

Re: A Lufthansa A350's frustrating Oakland diversion

#112

Post by ideator »

https://youtu.be/o7RId2iiZng?si=ERMLyrSwkrLL6xmh

Recently there was a separation issue with a very similar night time visual approach into SFO.

It's not like trying to squeeze two flights into close parallel runways at the same time to maximizer capacity is a very safe thing to do considering everything that could go wrong

Re: A Lufthansa A350's frustrating Oakland diversion

#113

Post by rsynnott »

babyshake wrote: post #35

This is coming from someone who only has experience as a commercial flight passenger, but I would expect AI to be very promising for ATC. Obviously there are various concerns ranging from potential attack vectors and the need for failsafes if any automated system fails, but has this been explored?

Oh, my, AI really is becoming the new blockchain, isn’t it?

Re: A Lufthansa A350's frustrating Oakland diversion

#114

Post by db48x »

ian-g wrote: post #72
markus92 wrote: post #58

Earlier quoted context omitted.

Pilot was bluffing. If they call an emergency, they can do whatever they want. But they can't just call a fuel emergency if they have enough fuel to divert to a viable alternate - that's not how the system is supposed to work. They're supposed to divert if they get close to minimum fuel and can't land at their primary airport. Of course, if it's a real emergency they can call any emergency (weather at alternate preve…

That would also mean it's really incredibly difficult to declare a fuel emergency around SFO, since Oakland and San Jose and (I guess, if it were really urgent) Moffat Field are all a five minute flight away, right?

The distance to the alternate really doesn’t matter much, because you always load enough additional fuel to divert to your alternate and land, plus more fuel called the “final reserve” which is enough to fly for another 30 or 45 minutes (depending on the airline and region). That amount of fuel is called the “minimum fuel”. If you get down to your minimum fuel and you aren’t actually landing at your destination yet, then you radio the controllers and tell them that you’re at minimum fuel and are diverting to your alternate. It is only time to declare an emergency if you get down to your final reserve, by which time you should already be at your alternate airport.

Also, you can’t really use the straight–line distance between airports to figure out how much extra fuel to bring, because you never end up flying that line. For one thing, you have to approach the airport from the correct direction so that you line up with a runway and so that you’re headed into the wind. For another, you have to get down from the altitude you were holding at to ground level. Between the two you need to go not towards the airport, but towards a spot far enough away from the airport that you can fly a gentle slope down towards the runway. You might even end up flying completely around the airport while descending before actually turning in and lining up with the approach runway.

Re: A Lufthansa A350's frustrating Oakland diversion

#115

Post by khuey »

antonjs wrote: post #102
kiratp wrote: post #78

Earlier quoted context omitted.

The FAA themselves recommend that foreign pilots do not use visual approaches at SFO. https://www.cbsnews.com/sanfrancisco/news/faa-wants-foreign-...

If I remember correctly, this Lufthansa flight usually arrives during the day, when the company permits visual approaches, but had a delayed departure, which is what let to their policy prohibiting visual approaches and the bad timing with the huge chain of other arrivals.

The flight's scheduled arrival time of 6:15 PM puts it well into darkness for much of the winter.

Re: A Lufthansa A350's frustrating Oakland diversion

#116

Post by gkedzierski »

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…

Did you mean visual approach, not VFR?

Re: A Lufthansa A350's frustrating Oakland diversion

#117

Post by ShadowBanThis01 »

kabes wrote: post #104
karcass wrote: post #33

I got my pilot's license in the Bay Area and transited SFO's class bravo frequently. The region has one of the world's most complex airspaces (a B, two Cs, and a crap-ton of Ds), and SFO has a mind-boggling amount of traffic for an airport of its size. Based on my lived experience in that airspace, I think ATC did the best they could in a tough position, and I think that Lufthansa asking for special treatment is the…

Lufthansa does what the FAA recommends and SFO had air canada almost landing on the taxiway because of the visual approach not too long ago. So calling it an asshole move is turning things around.

So punish everyone because of Air Canada's fuck-up?

Re: A Lufthansa A350's frustrating Oakland diversion

#118

Post by ShadowBanThis01 »

throwbadubadu wrote: post #107
trentnelson wrote: post #96

Earlier quoted context omitted.

That’s not how ATC works. First come, first served.

No, that's also not how it should work. Airports have a certain capacity, that's why you use slot allocations at crowded ones. You can say that day was so botched that they blew the one plane in fav of all the others, but that is not how it should work, telling a plane with an allocated slot you cannot even have a realistic estimate when we will fit you in.

The plane was hours late.

Re: A Lufthansa A350's frustrating Oakland diversion

#119

Post by db48x »

throwbadubadu wrote: post #107
trentnelson wrote: post #96

Earlier quoted context omitted.

That’s not how ATC works. First come, first served.

No, that's also not how it should work. Airports have a certain capacity, that's why you use slot allocations at crowded ones. You can say that day was so botched that they blew the one plane in fav of all the others, but that is not how it should work, telling a plane with an allocated slot you cannot even have a realistic estimate when we will fit you in.

You’re not wrong, but don’t forget that they were three hours late. This is really why airports operate on a first–come first–served basis; someone is always late.

Re: A Lufthansa A350's frustrating Oakland diversion

#120

Post by TaylorAlexander »

khuey wrote: post #115
antonjs wrote: post #102

Earlier quoted context omitted.

If I remember correctly, this Lufthansa flight usually arrives during the day, when the company permits visual approaches, but had a delayed departure, which is what let to their policy prohibiting visual approaches and the bad timing with the huge chain of other arrivals.

The flight's scheduled arrival time of 6:15 PM puts it well into darkness for much of the winter.

You know I thought you were right but apparently for that day sunset was 6:30PM.

https://www.timeanddate.com/sun/usa/san-francisco?month=10

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