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A Lufthansa A350's frustrating Oakland diversion

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Re: A Lufthansa A350's frustrating Oakland diversion

#51

Post by JAlexoid »

dxf wrote: post #13
kokken wrote: post #5

I’m sure the industry has standards for assigning blame, but it looks to me that ATC is clearly being assholes here. Even from this article that clearly seems to think Lufthansa is in the wrong I walked away with a feeling that ATC and small town cops are one and the same.

The current top comment on the article explains the situation, and ATC are "not being assholes here": >NorCal had a new interpretation of ILS approaches come down several months ago that tied the controllers hands with regards to ILS approaches during visual conditions... The controllers were issued guidelines that if it’s busy and an aircraft is unable to comply with the approaches advertised on the atis or maintain…

The ATC should have just told them that, from the get go. They know exactly how many aircraft are headed their way, the pilot doesn't

Re: A Lufthansa A350's frustrating Oakland diversion

#52

Post by CaliforniaKarl »

chris_va wrote: post #43
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…

I also fly a bit in the bay area ... ATC is supposed to accommodate to the best of their ability. Accommodating here could have been just waiting for a natural gap (which is what I think happened), but I think ATC should have just called Oakland center immediately and had a gap created for 10-20 minutes in the future. It is not like they were the only aircraft on the ILS approach that evening... Though, as I am not a…

The video posted by u/hansenq showed what flows were like, with traffic from the east sequenced as far out as Salt Lake City. It probably would’ve needed coordination with Oakland, LA, and Salt Lake centers

Re: A Lufthansa A350's frustrating Oakland diversion

#53

Post by CaliforniaKarl »

JAlexoid wrote: post #47
kayodelycaon wrote: post #19

Earlier quoted context omitted.

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

When flying and being responsible for an aircraft full of people - estimates take a very different meaning.

That’s why flight plans have diversion fields, with requirements to have enough field to get to the diversion airport, and even to hold _there_.

Re: A Lufthansa A350's frustrating Oakland diversion

#54

Post by CaliforniaKarl »

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?

Charted/Published visual approaches use the localizer part of the ILS equipment, and pilots have the option of using the glide slope.

“ILS” is equipment, but it’s also procedures and (increased) spacing (compared to visual separation).

Re: A Lufthansa A350's frustrating Oakland diversion

#55

Post by michael_j_x »

CaliforniaKarl wrote: post #50
michaeljx wrote: post #39

Earlier quoted context omitted.

From what I understand, despite the tower not being able to create a gap for 30+ minutes,which although extreme may be understandable due to SFO being the way it is, another major factor was the fact that the tower was unable to provide a realistic estimated time to enter the circuit. That is completely unacceptable.

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 a stock trader is expected to calculate PnL of their positions on the fly given the current stock price.

Re: A Lufthansa A350's frustrating Oakland diversion

#56

Post by CaliforniaKarl »

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…

One useful part of that video is how they play clips of ATC telling flights to “join the localizer”.

SFO has two published visual approaches (https://www.airnav.com/airport/KSFO, scroll to the bottom): Both visual approaches have pilots fly to intercept their runway’s localizer, the part of the ILS equipment that provides lateral positioning, relative to the localizer’s centerline (which is generally coincident to the corresponding runway’s centerline).

So, by flying the published visual approach and remaining “on the localizer”, you have separation from the planes on the parallel runway. What’s missing is careful monitoring and separation, and that’s what Lufthansa wanted.

It’s worth noting that SFO does have a Simultaneous Offser Instrument Approach procedure: See https://www.tc.faa.gov/its/worldpac/techrpt/afs420-84-1.pdf (detail) or https://www.flysfo.com/sites/default/files/PRM_SOIA_version_... (summary). But that procedure requires, among other things, additional controllers handling approach and monitoring. SFO might not have the spare controllers right now.

Re: A Lufthansa A350's frustrating Oakland diversion

#57

Post by raverbashing »

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…

> reason that Lufthansa wants ILS is to increase safety

Yes because "more technology is more better" right? And forgetting about how to do things by hand (or eye) doesn't pose a risk to anyone neither

A visual approach is no more unsafe than an ILS one in good weather. Sure, ok, the caveat here is "at night" but I don't think the multiple pilots that were doing it at the time were being risky on purpose

(and people are quoting Asiana, but understand that fumbling a visual approach landing is not a thing that should be common)

Re: A Lufthansa A350's frustrating Oakland diversion

#58

Post by markus92 »

reso wrote: post #45

> Pilot: If we are not set up for base soon, we will have to declare a fuel emergency and that would really fuck up your sequence. > Controller: What is your divert field? > Pilot: Oakland > Controller: Ok you need vectors to Oakland? > Pilot: No, my company forbids visual separation at night, what is the problem here? > Controller: I can't have this conversation with you. You either divert to Oakland or you can cont…

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 preventing them from landing there for example), but not threaten a controller to call an emergency just to get priority handling at their primary.

The controller knew that and just called it. A diversion is a major annoyance but not a safety issue.

Re: A Lufthansa A350's frustrating Oakland diversion

#59

Post by DiggyJohnson »

reso wrote: post #45

> Pilot: If we are not set up for base soon, we will have to declare a fuel emergency and that would really fuck up your sequence. > Controller: What is your divert field? > Pilot: Oakland > Controller: Ok you need vectors to Oakland? > Pilot: No, my company forbids visual separation at night, what is the problem here? > Controller: I can't have this conversation with you. You either divert to Oakland or you can cont…

Those aren’t the options presented, you’re being dramatic. The pilot has the options to wait or divert, no matter what the controller says, in any situation where they cannot get into an airport.

There is no risk of crashing here. The pilot cannot call the controllers bluff and declare a fuel emergency to land at SFO because Oakland is so close and it would be unprofessional.

The controller doesn’t have time to explain why the previous estimate was wrong or discuss company policy.

Re: A Lufthansa A350's frustrating Oakland diversion

#60

Post by Analemma_ »

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…

> I'm actually surprised SFO still allows visual approaches at night after that Air Canada 759 flight nearly landed on the taxiway ~5 years ago

The Air Canada incident happened because one of the runways at SFO was closed for maintenance, and after it happened the FAA specifically updated their regulations to require ILS when there's a possibility of runway confusion. There's no reason to think VFR landings at SFO are unsafe in normal conditions.

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