Comment by AceyMan

Comment by AceyMan 4 days ago

31 replies

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Under FAA rules this was a screwup. [edit: see my own reply] (However, the rules are subtle, so they can be partially forgiven.) However, I'm not only a dispatcher but also a philosophy BA, so I've found a good way to explain it.

Your reserve fuel (the "extra" fuel over what the actual flight burn) can of course be used (hello, that's what it's there for) but—and here's the rub—you can never plan on using it.

That is to say, in this case, when they missed their first or second approach, they CANNOT say, "We'll use our reserve fuel and make another go at it" because that would be intentionally planning to burn your reserve.

You may only dip into your reserve when you have no other choice. In this case, when the only fuel they had left was reserve, they are obligated by law to proceed to the alternate airport, which clearly they did not do [correction: they did do the proper thing; see my 2nd reply below]. No bueno.

[this is a slight simplification (minor details omitted for brevity) but the kernel of the issue is properly described]

AceyMan 4 days ago

Update: OK, if *Edinburgh* was their alternate and they missed there and were then forced to bugout for Manchester, that's then an example of when reserve is OK to be burned. (The 'slight simplification' I omitted was unpacking how the alternate fuel plays into the process, but here, that was a key part of the series of events.) That's what I get for not reading TFA first :-/

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  • behringer 4 days ago

    Not really, you should have enough fuel to make it to multiple alternatives or make emergency landing somewhere else. You should never burn that last 45 mins unless you want to make the news and file a lot of paperwork.

    Reply View 2 replies
    • mmaunder 4 days ago

      The regs are quite specific on if and when we need an alternate, which is weather dependent, and what your fuel requirements are. And we don't really have the idea of "multiple alternatives", but I guess it's implied by the additional reserve - what us Americans call a reserve or the Europeans call "final reserve". In case you're curious, we use the TAF (termimal area forecast) to determine if we need an alternate, and use a 1,2,3 rule which is 1 hour before and 1 hour after arrival time we need ceilings of at least 2000 ft and 3 statute miles of horizontal visibility.

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    • hshdhdhehd 4 days ago

      Er.. and maybe crash and kill yourself, all your passengers and crew and people on the ground.

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  • AceyMan 4 days ago

    [flagged]

    Reply View 11 replies
    • scrumper 4 days ago

      I'm curious why you did that? It's not a very complicated sequence. The whole point of engaging in a discussion here is to think about the issues raised and offer a point of view while incorporating other perspectives into yours. You've spent your money to bypass the whole intent of this site; akin to you being hungry then sending someone else to a restaurant for you so you can later read their review of the food.

      EDIT and you of most of the commenters here, with your industry background, are better placed to offer an opinion!

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      • Hackbraten 4 days ago

        > It's not a very complicated sequence.

        For me, it was. I have trouble forming a mental model of itineraries so I’m grateful for the summary.

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        • [removed] 4 days ago
          [deleted]
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      • AceyMan 4 days ago

        Why? I saw no upside to reading a layman's media source and teasing out the sequence, which is all I wanted to know. I read NTSB reports for pleasure and my favorite YT creator is Blancolirio. There's an infintesimal chance that the story had any juicy details I cared about. Also, it was work hours and I really didn't have any more time to devote to topic. I was in a rush to get my take out there, since I am a legitimate SME.

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      • whycome 4 days ago

        I think you missed the point.

        Presenting information in different ways is useful (and the method of display can offer informational insights itself). And for different users it might help parse larger connections. And by using the LLM to summarize just that one facet of the problem (itinerary and sequence) and sharing it here, they’ve contributed in a meaningful way. It may not have warranted a response. But it added to overall understanding of the problem space to help facilitate discussion. And they did well enough by citing that the info came from an LLM. They didn’t bypass the intent of the site. They added to it and fell right in line with that intent.

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    • Hackbraten 4 days ago

      Thanks, I appreciate it!

      Even though I’ve read the entire article, I found it very difficult to mentally visualize and ended up not noticing that there were three destination airports involved.

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mmaunder 4 days ago

"Under FAA rules this was a screwup."

Not necessarily. And I get that you've caveated yourself with an edit and a reply etc, but lets assume that you're not hedging for the moment.

They carried required reserves on departure. Multiple approaches thwarted by extreme unforseen weather. They declared Mayday Fuel, which is mandatory under EASA regulations, when reserve fuel use became unnavoidable. They diverted to the nearest suitable airport.

Landing with 220kg is close, but within bounds of a declared fuel emergency.

Crew decision to declare Mayday and divert was proper airmanship, not negligence.

Yes, reserve fuel may not be planned for. But it may be used. It's there for a reason. Your accusation doesn't account for dynamic evolving weather and realtime decision making.

I'm an instrument rated pilot and an advanced ground instructor under FAA and I fly IMC in bad weather as single pilot IFR around the pacific northwest and colorado.

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  • qazxcvbnmlp 4 days ago

    This is the right answer.

    Was this good/bad? Idk Room for improvement? Maybe? Clearer direction with the benefit of hindsight? Maybe. but the majority of the sentiment in the responses is coming from people not type rated in a 737.

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  • rjh29 3 days ago

    Some commenters are claiming the flight should have never taken off and that the weather situation was entirely predictable. What's your take on that?

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    • inoffensivename 3 days ago

      Generally, if it's legal to take off, we're going.

      (Source: am airline captain)

      Reply View 0 replies
crazygringo 4 days ago

> That is to say, in this case, when they missed their first or second approach, they CANNOT say, "We'll use our reserve fuel and make another go at it" because that would be intentionally planning to burn your reserve.

Is that what happened? That's not in the article, what's the source?

And other comments here are saying the third attempt was in Edinburgh, so they were already trying to land anywhere possible by the third attempt.

At what point are you saying they chose to plan on using reserves when they still had any option for landing without reserves?

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  • whycome 4 days ago

    OP didn’t have the full picture. They’ve offered appropriate edits/updates

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dclowd9901 4 days ago

> you can never plan on using it

In off-roading, we have a similar rule with 4 wheel drive. You don't use it to go in, you use it to get out.

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yieldcrv 4 days ago

in what way do FAA rules apply to operators doing a European to UK flight in an airline that doesn't operate in the US?

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  • mmaunder 4 days ago

    Similar philosophies but with differences. e.g. FAA reserve requirements is destination + alternate + 45 mins reserve. EASA is destination + alternate + final reserve which is 30 mins holding for jets and 45 mins for pistons IIRC. But in both cases it's that idea of a destination, an alternatite, and additional. And then there's the requirements around whether you need an alternate, etc.

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  • averageRoyalty 4 days ago

    I was wondering that too. I've taken it to mean "if this situation had happened in the Americas..." as the most generous interpretation I can make.

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themafia 4 days ago

If you're into your reserves you should declare an emergency immediately to get priority in air traffic sequencing and control.

Pilots may be organizationally disincentivized when making this decision.

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  • mmaunder 4 days ago

    It's required when using your reserve under EASA to declare Mayday Fuel.

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octo888 4 days ago

> Under FAA rules this was a screwup

An oversight I'm sure they can fix ;-)

FAA as a yardstick? Hm

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