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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

#201

Post by connorlu »

jacquesm wrote: post #181
MaxikCZ wrote: post #174

Earlier quoted context omitted.

4 replies and 3 are dismissing even the idea.. Yes, you get "some" back, and its not negligible amount. Typical modern airliner can descend on 15-20:1, giving you over 150-200km (90-120mi) range from typical cruising altitude of 33 000 feet even with engines off. Most everyday descents are actually done by maintaining altitude as long as possible, and then iddling the engines fully for as long as clearance allows. (O…

(1) this was a jet, not a turboprop Edit: changed turbofan into turbprop, which is what I meant. (2) fuel burned stays burned, you don't 'get it back' (3) the altitude gained may have been adjusted to account for the low fuel situation (4) the winds are a major factor here, far larger than the fact that 'what goes up must come down', something that is already taken into account when computing the fuel reserve in the…

The 737-800 uses CFM56-7 turbofan engines.

[1] https://en.wikipedia.org/wiki/CFM_International_CFM56#CFM56-...

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

#202

Post by cibyr »

gmanley wrote: post #131
nickff wrote: post #84

Earlier quoted context omitted.

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...

That example is so well known due to how exceptional it was, especially how the pilots handled it. Robert Pearson, the captain, was a very experienced glider pilot. That's something that not many commercial pilots have. There were also two factors in the landing, that allowed for this to happen. You're going to be coming in really fast for a landing, when gliding in a commercial jet, and you don't have access to your…

The "scraping helped slow it down" theory makes no sense to me. What do you think has a higher coefficient of friction - tire rubber on asphalt, metal on asphalt, or metal on metal?

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

#203

Post by fidotron »

alwa wrote: post #199
fidotron wrote: post #111

Earlier quoted context omitted.

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…

It’s generous of the classifying authority to send to the ICAO meeting somebody both appropriately credentialed to know about the information in question, and willing to talk coyly about it. Did these additional incidents inform the policy discussions at the meetings you attended?

It's funny you say that, because the way it happened was it was blurted out by a diplomat from a certain country, at which point most of the regulators facepalmed and all of those of us from outside were having the same reaction as many here.

The whole subject of discussion prior to this was efforts to improve data sharing wrt incidents.

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

#204

Post by maccard »

jacquesm wrote: post #26
simplicio wrote: post #9

Earlier quoted context omitted.

Assuming it wasn't just luck, it seems impressive they managed to maximize their (landing attempts/fuel reserves) ratio like that.

They got within a hair of crashing, there is nothing impressive about this. 30 minutes, ok, you still get written up but this is cutting it way too fine.

> this is cutting it way too fine.

Either this is true, or this is why there’s a 45 minute reserve requirement. There were three failed landing attempts in two airports prior to the successful landing, and they spent almost as much time attempting to land as the scheduled flight took.

Seems like this was exactly the scenario it was designed for?

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

#205

Post by eCa »

deadbabe wrote: post #38

On the positive side, if they had made a crash landing with so little fuel, there would not likely have been a fiery explosion, and many more passengers would have survived than normal?

> and many more passengers would have survived than normal?

This[1] kind of crash landing is very rare (in that case there was no fire despite being immediately after take off, perhaps because of the cold). Normally an outcome like this is only reasonable to expect if you actually reach a runway despite being out of fuel. Like Gimli[2].

[1] https://en.wikipedia.org/wiki/Scandinavian_Airlines_System_F...

[2] https://en.wikipedia.org/wiki/Gimli_Glider

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

#206

Post by [deleted] »

geor9e wrote: post #170
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…

Do forecasted storms go into the fuel estimate formulas?

[deleted]

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

#207

Post by nradov »

SJC_Hacker wrote: post #153
nradov wrote: post #129

Earlier quoted context omitted.

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

> Which specific civil aviation incidents are covered by some secret classification? You would have to have secret clearance to know which ones

It's cool, I have Top Secret Level 3 (Omega Sector) clearance so you can go ahead and tell me.

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

#208

Post by inglor_cz »

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.

"claiming they're low on fuel"

It is almost fascinating how humans will stoop to dishonesty even in banal situations - and not just any humans, but pilots, who should be subject to at least some vetting.

Maybe planes should be retrofitted as to transmit their actual fuel state including a qualified assessment in minutes to the ATC. Not just because of the cheaters, but also to warn the ATC in the rare case that some plane crew isn't very assertive about their dwindling fuel, or hasn't noticed the problem.

It would make prioritizing the queue a bit more neutral.

If I designed such a system from scratch, "remaining fuel" would be part of my telemetry.

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

#209

Post by alwa »

jacquesm wrote: post #181
MaxikCZ wrote: post #174

Earlier quoted context omitted.

4 replies and 3 are dismissing even the idea.. Yes, you get "some" back, and its not negligible amount. Typical modern airliner can descend on 15-20:1, giving you over 150-200km (90-120mi) range from typical cruising altitude of 33 000 feet even with engines off. Most everyday descents are actually done by maintaining altitude as long as possible, and then iddling the engines fully for as long as clearance allows. (O…

(1) this was a jet, not a turboprop Edit: changed turbofan into turbprop, which is what I meant. (2) fuel burned stays burned, you don't 'get it back' (3) the altitude gained may have been adjusted to account for the low fuel situation (4) the winds are a major factor here, far larger than the fact that 'what goes up must come down', something that is already taken into account when computing the fuel reserve in the…

(1) The turbofan category of jet engine seems to inspire a lot of very pretty animated technical diagrams—here’s one set from a German manufacturer [0]. Now if only we could convince Bartozs Ciechanowski to take on such a subject… [1]

(2) I know glider pilots who fly without any fuel at all, once aloft… sounds not unlike the 150-200km glide range that @MaxikCZ mentions at idle from cruising altitude.

[0] https://aeroreport.de/en/good-to-know/how-does-a-turbofan-en...

[1] e.g. https://ciechanow.ski/airfoil/

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

#210

Post by whycome »

scrumper wrote: post #142
jacquesm wrote: post #77

Earlier quoted context omitted.

> They had 6 more minutes to do that touch and go around if that happened 6 minutes is way out of the comfort zone. They might not have made it in that case.

Correct, article says they landed with 220kg which is around 6 minutes of average fuel burn over an entire flight - bit less at cruise, a hell of a lot more at takeoff/climb. So I don't think 220kg is enough to do a go-around in a 737 (well, a go-around would've been initiated with a bit more than 220kg in the tank - they burned some taxing to the gate - but you get my point.) I've read around 2,300kg for takeoff and…

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