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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

#521

Post by inglor_cz »

sebzim4500 wrote: post #507
inglor_cz wrote: post #305

Earlier quoted context omitted.

You mean that ATC would abuse their position by making planes circle as long as they have some fuel left?

No I mean people would take off with less fuel so that by the time they reach their destination they could skip the queue

This is provable, though (there are regulations that say how much fuel you must have at takeoff - enough to divert comfortably to a suitable airport + some reserve for circling), and could be heavily punished. Up to the withdrawal of necessary licences.

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

#522

Post by anonymars »

kqr wrote: post #436
howard941 wrote: post #347

Earlier quoted context omitted.

The glider guys would always suggest a forward slip. It's a lot of fun to do. It's not taught often enough during primary training for powered airplanes.

Aren't low-speed slips something that makes planes flip upside-down when not used very carefully? (Inadvertent rudder changes corrected with opposite aileron resulting in a snap roll.)

You're probably thinking of a skid, which is when you put too much rudder in the same direction as the ailerons. Then the lower (and slower because it's on the inside) wing stalls first (and goes lower still) and away you go. Often when turning to land, so there's not enough altitude to recover.

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

#523

Post by howard941 »

kqr wrote: post #436
howard941 wrote: post #347

Earlier quoted context omitted.

The glider guys would always suggest a forward slip. It's a lot of fun to do. It's not taught often enough during primary training for powered airplanes.

Aren't low-speed slips something that makes planes flip upside-down when not used very carefully? (Inadvertent rudder changes corrected with opposite aileron resulting in a snap roll.)

Yes, being that one is cross-controlled they must be used very carefully. It's really obvious that one is cross-controlling. It's the only time outside of really powerful crosswinds that you see what's below and ahead of you out of the side window. That view is what makes it fun.

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

#524

Post by tclancy »

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?

Username checks out. I don’t think the fire is your first concern in a plane crash.

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

#525

Post by mercutio2 »

mierz00 wrote: post #464
ant6n wrote: post #300

Earlier quoted context omitted.

The greenhouse effects of flying is about 3-5x the effect of just burning the fuel.

Could you explain why this is?

Water vapor in the stratosphere has a very high radiative forcing. Offset somewhat by particulates in the upper atmosphere.

Cirrus clouds and contrails have a distinct, and large, additional forcing.

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

#526

Post by nerdawson »

octo888 wrote: post #519
stockresearcher wrote: post #191

The only real question for the inquiry is how the decision was made to divert to Edinburgh and whether that was a reasonable decision at the time.

And then from Edinburgh to Manchester (184 miles) instead of Newcastle (91 miles) or Teeside (125 miles), both airports Ryanair operate out of.

Most of the trains north between Preston and Glasgow were being cancelled that day due to the weather. Perhaps knowing they only had one more attempt at landing safely left, Manchester further south seemed like the better bet.

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

#527

Post by raviolo »

heelix wrote: post #403
gsnedders wrote: post #67

Earlier quoted context omitted.

As others have said, final fuel reserves are typically at least half an hour, and you shouldn't really be cutting into them. What if their first approach into MAN had led to another go around? With a major storm heading north-easterly across the UK, the planning should have reasonably foreseen that an airport 56 miles east may also be unavailable, and should've further diverted prior to that point. They likely used t…

Suspect they were IFR. All your points stand. First time flying things with a jet engine, I was shocked how much more fuel gets burned at low altitude. It almost always works out better to max climb to altitude and descend than to fly low and level. On a small jet, things can get spicy fast when ATC route you around at 5000' for 15 minutes or so. Three aborted landings would gobble gas like crazy. § 91.167 Fuel requi…

They were most definitely IFR. Not because of the weather but because IFR is required above certain altitude 18,000 ft in the U.S. and typically lower in Europe (depends on a country). Jets including small private jets are almost always on IFR. Airliners with passengers - always.

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

#528

Post by tamcap »

Reason077 wrote: post #495
tamcap wrote: post #105

Earlier quoted context omitted.

Not really. While you have a large potential energy buildup at a higher altitude, you cannot "bank it" / "save it" on descent. There is no way to store it in batteries or convert it back into fuel. One of the challenges of aeronautics is the efficient disposition of the potential energy without converting it all into kinetic energy (ie speed) so that the landing happens at an optimally low speed - thus giving you a c…

> "While you have a large potential energy buildup at a higher altitude, you cannot "bank it" / "save it" on descent. There is no way to store it in batteries or convert it back into fuel." An electric fan aircraft absolutely can recharge it's batteries on descent. The fans simply act as turbines, creating drag to slow the aircraft and electricity to charge the batteries. Large commercial airliners already have a sma…

You can use a turbine to generate electricity, so yes, you are converting potential energy into electrical potential. However, no real mass produced passenger plane today can use that electricity for flight (thrust).

RAT is only used when sh*t hits the fan. Even then, it can help you power some hydraulics / electrical, not “store” energy for further flight.

The OP asked - in a low fuel situation, can the energy spent on a climb get effectively recovered - and the answer is not really. We convert as much as we can into unpowered (low-powered) descent. But once you are at a spot where you make a final decision to land or not, you are by design low and slow - and all that energy you had 15m ago is gone.

If you need to keep flying, those engines need to spool back up. And that takes fuel.

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

#529

Post by rkomorn »

tamcap wrote: post #528
Reason077 wrote: post #495

Earlier quoted context omitted.

> "While you have a large potential energy buildup at a higher altitude, you cannot "bank it" / "save it" on descent. There is no way to store it in batteries or convert it back into fuel." An electric fan aircraft absolutely can recharge it's batteries on descent. The fans simply act as turbines, creating drag to slow the aircraft and electricity to charge the batteries. Large commercial airliners already have a sma…

You can use a turbine to generate electricity, so yes, you are converting potential energy into electrical potential. However, no real mass produced passenger plane today can use that electricity for flight (thrust). RAT is only used when sh*t hits the fan. Even then, it can help you power some hydraulics / electrical, not “store” energy for further flight. The OP asked - in a low fuel situation, can the energy spent…

> RAT is only used when sh*t hits the fan.

Isn't it when air hits the fan, technically?

(Sorry.)

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

#530

Post by jacquesm »

lo0dot0 wrote: post #516
jacquesm wrote: post #37

Earlier quoted context omitted.

The incident investigation will surely focus on exactly those things. But: just like shipping aviation is at the mercy of the weather and even though the rules (which are written in plenty of blood) try to anticipate all of the ways in which things go wrong there is a line beyond which you are at risk. I've had one triple go-around in my life and it soured me on flying for a long time afterwards because I have writte…

There must be measurements of the fuel tanks state, right?

There are but this is not as precise as you might think due to a lot of confounding factors. Even the best flow meters are only about 0.2% accurate, and I find that seriously impressive.
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