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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

#241

Post by warmwaffles »

dcchambers wrote: post #192
rappatic wrote: post #136

> the Boeing 737-800 had just 220kg of fuel left in its tanks... enough for just five or six minutes of flying Maybe I'm just unaware, but it's crazy to me that these planes burn 40 kilograms of jet fuel per minute.

Especially crazy considering the 737 is not a particularly large commercial aircraft. 40kg/minute is around 12 gallons (47 liters) of fuel per minute. Meanwhile a 777 burns around 42 gallons (160 liters) per minute. A 747 burns 63 gallons (240 liters) per minute - more than a gallon per second!

Is that at cruising altitude?

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

#242

Post by jacquesm »

gmanley wrote: post #221
cibyr wrote: post #202

Earlier quoted context omitted.

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?

I would hesitate to chalk it up to just theory, given it was in the NTSB report and they don't really mess around with throwing baseless stuff around. I'd be interested to take another look at it. They likely go into the material science and physics behind this very thing. They're usually filled with gems. You also have to keep in mind, it wasn't just rubber against asphalt, it was rubber on a wheel that spins. I'm n…

They could have died. The nosewheel assembly being pushed up through the floor of the cockpit has killed more than one pilot.

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

#243

Post by cosmicgadget »

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?

Well there'd probably be a fire but not a sustained fire which would improve survivability.

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

#244

Post by db48x »

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…

No, you don’t magically get the fuel back. But you do get a lot of the _kinetic energy_ back, and that energy keeps you flying without having to burn yet more fuel. You burn a lot of fuel while climbing, but then hardly any at all while descending. And that descent might cover 100 miles across the ground.

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

#245

Post by huijzer »

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'd be very wary to get ahead of the investigation and make speculative statements on how this could have happened, the one thing that I know for sure is that it shouldn't have happened, no matter what.

Just watch Juan Browne, he usually turns out pretty good in analyzing the mishaps. He didn’t upload anything for Manchester yet but will probably soon: https://youtube.com/@blancolirio

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

#246

Post by devilbunny »

alwa wrote: post #209
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) 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://aero…

Aircraft that are designed as gliders are much lighter and thus have much longer glide range than aircraft that aren't. They're so lightweight that they can climb on thermals. A 737 is not going to be able to do that, but a regular glider can't fly at 400 knots.

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

#247

Post by phyzome »

rappatic wrote: post #136

> the Boeing 737-800 had just 220kg of fuel left in its tanks... enough for just five or six minutes of flying Maybe I'm just unaware, but it's crazy to me that these planes burn 40 kilograms of jet fuel per minute.

Yeah, when people say "flying has a high carbon footprint", they're not kidding. It's really quite massive.

I don't fly any more.

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

#248

Post by isaacdl »

bluGill wrote: post #169
behringer wrote: post #88

Earlier quoted context omitted.

With 6 minutes left everyone could have died if anything went wrong with the final landing, even a gust of wind could have ended everybody's life.

Could have, but pilots practice no fuel landings all the time (in simulators). If they can get to ground that is "level enough" nobody dies. It is not something you ever want to see in the real world (and in the real world people often do die when it happens), but it isn't automating people die.

I don't think that's all that true for airliners. Pilots definitely practice for engine-out scenarios during all levels of training up to the airlines, but the ability of a plane the size of a 737 to safely land on anything but a runway is...limited. And if you're low, slow, and trying to go around, that's not a lot of time to glide to ground that is "level enough".

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

#249

Post by jacquesm »

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?

Yes. Even not forecasted storms in the form of a probability of wind at low altitude when the engines are at their least efficient. And tradewinds at altitude, which are quite variable as well.

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

#250

Post by gregoriol »

gsnedders wrote: post #120
gregoriol wrote: post #57

Earlier quoted context omitted.

Flight from Edinburgh to Manchester is just a bit more than 1 hour, so after trying 2 landings, diverting to Edinburgh (15-20 minutes flight), 1 more landing attempt, well, you get very close to 2 hours.

I felt like that seems a little long from EDI to MAN (after all, EDI to LHR is typically a flight time of under an hour!), so: https://globe.adsbexchange.com/?icao=4d2256&lat=54.720&lon=-... is the track of this flight. Went around at EDI at about 19:10Z, landed at about 19:51Z, so about a 41 minute flight.

Right, I probably got the information for flight time as seen by a passenger on a ticket, not for a plane already flying. Thanks!
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