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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

#211

Post by mrguyorama »

dTal wrote: post #85
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.

You get that energy back on descent, no?

Some of it. The air density is an important part of efficiency at higher altitudes, so every moment spent under like FL320 is wasted fuel.

So the entire climb "up", you are also wasting energy fighting the thick air. On the way back "down", that air again fights you, even though you are basically at idle thrust.

Your fuel reserves are calculated for cruise flight, so time spent doing low altitude flying is already at a disadvantage. "Two hours of reserves" is significantly less than that spent holding at a few thousand feet. Fuel efficiency while climbing is yet again dramatically worse

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

#212

Post by MadnessASAP »

constantcrying wrote: post #115
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 a little confused by what there is to investigate at all. One of the most important aspects of taking safety seriously is that you do not just investigate things which had an impact, but that you proactively investigate near misses (as was the case here) and even potential incidents. A plane with 6 minutes of fuel left is always a risk to every person on board and potentially others if an emergency landing becom…

Indeed that is the definition of a "aviation incident" where there was a risk of injury or damage. If there is actual injury or damage it becomes an "accident".

The investigations into incidents aren't usually particularly long or noteworthy and often the corrective action will be to brief X on dangers of Y, or some manner of bulletin distributed to operators.

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

#213

Post by cosmicgadget »

loverofhumanz wrote: post #79
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 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.

Although credit is due to fuel reserve policies considering they landed after two diversions and three go arounds.

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

#214

Post by [deleted] »

FireBeyond wrote: post #195
jacquesm wrote: post #181

Earlier quoted context omitted.

(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 - a turbofan is a subset of jet engine, and there are no 738s running anything other than a turbofan. Actually, nothing in civil aviation that has a "jet engine" has used anything but a turbofan (or turboprop) since the early 70s with the exception of Concorde and some older business jets. (Turboprops are jet engines, too, to be precise, with the jet of exhaust gases powering the propeller.)

[deleted]

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

#215

Post by inglor_cz »

mrguyorama wrote: post #187
lenerdenator wrote: post #139

Earlier quoted context omitted.

Perhaps. If the pilot knows that the ATC can see he's full of it, he might be less likely to lie. Those who still do can be grounded and be moved into management or take up a career in politics.

Putting a theory of "you shouldn't trust pilots" into ATC breaks the entire system. It is a system built out of very regulated parts, very professional people, and tight controls. Pilots are encouraged to be very forward and proactive about fuel situations because of https://en.wikipedia.org/wiki/Avianca_Flight_052 Minimum fuel requirements are calculated as "Time of fuel for cruise to certain points", which is usual…

"It is a system built out of very regulated parts, very professional people, and tight controls."

Locally, this is true. Globally, not so much. I remember my friend's vivid description of a flight taken in Nepal. It was absolutely wild.

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

#217

Post by whycome »

scrumper wrote: post #163
AceyMan wrote: post #126

Earlier quoted context omitted.

[flagged]

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. ED…

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.

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

#218

Post by cosmicgadget »

YeahThisIsMe wrote: post #58
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 remember this stuff being a bigger story for a short moment x years ago, where low cost carriers (it might have been Ryanair then, too) routinely flew with unreasonably small amounts of "backup" fuel and had to declare emergencies in order to get on the ground safely. I guess they're trying it again now that the whole thing had blown over.

Pretty obviously not the case here if you read the article.

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

#219

Post by smaudet »

cibyr wrote: post #202
gmanley wrote: post #131

Earlier quoted context omitted.

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?

Don't forget the surface area of contact...

Rubber likely grips much better than metal, however three wheels have massively lower surface area than the body of the plane, or even a small section of it like the head.

Of course we don't land tireless for other reasons (metal transfers heat exceptionally well unlike rubber, paint doesn't survive high speed impact, and it tends to deform upon impact with anything, making any future flights unsafe), but the fastest way to slow down if you don't care about safety or comfort would probably be to land tireless, if you could introduce some rotational spin, that might be faster (more force directed in multiple directions).

Also, on the note of "coefficient of friction", remember that this number is not just some innate property of a molecule - as the metal scratches the pavement and deforms, its coefficient of friction goes up as micro-deformities accrue.

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

#220

Post by whycome »

crazygringo wrote: post #93
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…

> 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…

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