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Ryanair flight landed at Manchester airport with six minutes of fuel left

theguardian.com

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Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#121

Post by jacquesm »

kube-system wrote: post #100
abtinf wrote: post #40

Earlier quoted context omitted.

Naively as an outsider, this situation seems like everything worked as intended? On a nominally 2h45m flight, they spent an extra 2 hours in the air, presumably doing doing fuel intensive altitude changing maneuvers, and were eventually able to land safely with their reserves almost exhausted. I’m a little confused by what there is to investigate at all. How much fuel should they have landed with?

I'm not an aviation expert, but generally in safety engineering, safety buffers are not simply calculated as [normal situation] * [safety factor], but [worst case scenario] * [safety factor] If you ever cut into your safety allowance, you've already fucked up. Your expected design criteria should account for all use cases, nominal or worst-case. The safety factor is there for safety, it is never intended to be used.

This is exactly how it is in this case. Any consumption of the fuel reserve would result in an investigation, this is a very extreme case and it may even result in a change in the rules depending on the root cause.

Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#122

Post by lenerdenator »

fidotron wrote: post #87
jacquesm wrote: post #23

That is very exceptional. I've written fuel estimation software for airliners (cargo, fortunately), and the number of rules regarding go-arounds, alternates and holding time resulted in there usually being quite a bit of fuel in the tanks on landing, by design. I've never heard of '6 minutes left' in practice where it wasn't a massive issue and the investigation into how this could have happened will make for interes…

I have known former air traffic controllers that won't fly certain airlines because of a notorious habit some have for queue jumping by claiming they're low on fuel. If they are low on fuel is something else, but in any case when the ATCs have noticed a pattern then something is up. This situation sounds a lot less nefarious, but it does also sound like they should have rerouted earlier.

Kinda surprised there's no data link for that sort of telemetry so that you don't necessarily have to take the pilot's word for it.

Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#123

Post by jacquesm »

ktallett wrote: post #98
bluGill wrote: post #70

Earlier quoted context omitted.

Sure, but the flight was a lot longer than planed. How much extra do we need. They declared an emergency, and thus put themselves at the front of the line. They had 6 more minutes to do that touch and go around if that happened, and since they were already in a low fuel emergency they get priority and so there is enough time to do that if they needed. (edit - as others have noted, 6 minutes with high error bars, so t…

Surely the issue is more that they decided to make so many attempts to land local. There should be a max level of attempts.

There is a lot of pressure on pilots to land local. But 3 go-arounds happens, not often, but it does.

Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#124

Post by Ekaros »

abtinf wrote: post #40
jacquesm wrote: post #23

That is very exceptional. I've written fuel estimation software for airliners (cargo, fortunately), and the number of rules regarding go-arounds, alternates and holding time resulted in there usually being quite a bit of fuel in the tanks on landing, by design. I've never heard of '6 minutes left' in practice where it wasn't a massive issue and the investigation into how this could have happened will make for interes…

Naively as an outsider, this situation seems like everything worked as intended? On a nominally 2h45m flight, they spent an extra 2 hours in the air, presumably doing doing fuel intensive altitude changing maneuvers, and were eventually able to land safely with their reserves almost exhausted. I’m a little confused by what there is to investigate at all. How much fuel should they have landed with?

Only issue I see is that should there have been stricter rules to diverting way earlier. If winds were such as to make landing harder. Would just directly going somewhere else been the correct choice to force.

Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#125

Post by NoiseBert69 »

blizkreeg wrote: post #96

As a naive person, I have a simple question - why would they even fly to an airport where there's 100mph winds? Wouldn't ATC know this and tell the flight way in advance to fly to a different destination?

Forecasts are based on multiple weather simulation runs.

It's a often good working gamble that you will pick a short period of weather that is within your operational limits.

Commercial pilots don't have "personal limits". It's defined by their airplane and/or companies constraints.

Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#126

Post by AceyMan »

AceyMan wrote: post #94
AceyMan wrote: post #68

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…

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 :-/

[flagged]

Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#127

Post by troupo »

nickff wrote: post #84
loverofhumanz wrote: post #79

Earlier quoted context omitted.

"I’m a little confused by what there is to investigate at all." You're confused why they should investigate how everyone on that flight came within minutes of dying? Something about the fuel reserves, procedures, or execution was clearly flawed.

Fuel depletion is risky, but not that risky; see the Gimli Glider for a case much more dangerous than this, which still worked out amazingly well. Edit: Here is the Wiki on incidents... https://en.wikipedia.org/wiki/Fuel_starvation_and_fuel_exhau...

You could've read at least the Wikipedia page on how miraculous Gimli Glider was.

From "all engine failure is never expected and not covered in training" to "Pearson was an experienced glider pilot familiar with techniques rarely needed in commercial flights" to the amount of maneuvers they had to execute on a barely responding aircraft

Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#128

Post by nostrademons »

cpncrunch wrote: post #102
jacquesm wrote: post #75

Earlier quoted context omitted.

Just reaching altitude again to make it to the first and later second alternate are mostly likely the biggest factors in the extra fuel consumption. That's very expensive.

The 30 min reserve is on top of the fuel needed to reach the alternate and do a landing there, so only the flight to the second alternate, plus the 2nd and 3rd landings at the initial destination would have cut into the reserve.

With 100mph winds I could easily see the 30 min reserve being eaten up by the flight from Edinburgh to Manchester. It's 178 miles! It takes a good 15-20 minutes to cross that distance when flying normally, add ascent & descent time and the landing pattern and you're easily at 24 minutes.

Edit: in other comments here, it seems like Edinburgh to Manchester is a 45 minute flight. So yeah, they could easily have been outside of reserves when they did the go-around at Edinburgh and still had only 6 minutes left at Manchester.

Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#129

Post by nradov »

fidotron wrote: post #111
kpmcc wrote: post #92

Earlier quoted context omitted.

Which airlines? I feel like if this is an issue we should be naming names.

No way. Having attended meetings at ICAO I can also tell you many details of various aviation incidents, including their existence, are covered by some secret classification. This fact being disclosed caused most of the attendees to lose all hope in the rest of the proceedings. To their credit the FAA reps on that occasion were by far the most reasonable gov representatives in the room, and the FAA are one of the maj…

Which specific civil aviation incidents are covered by some secret classification?

Re: Ryanair flight landed at Manchester airport with six minutes of fuel left

#130

Post by jacquesm »

Ekaros wrote: post #124
abtinf wrote: post #40

Earlier quoted context omitted.

Naively as an outsider, this situation seems like everything worked as intended? On a nominally 2h45m flight, they spent an extra 2 hours in the air, presumably doing doing fuel intensive altitude changing maneuvers, and were eventually able to land safely with their reserves almost exhausted. I’m a little confused by what there is to investigate at all. How much fuel should they have landed with?

Only issue I see is that should there have been stricter rules to diverting way earlier. If winds were such as to make landing harder. Would just directly going somewhere else been the correct choice to force.

This is likely one of the questions the investigation will focus on.
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