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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

#581

Post by anonymars »

howard941 wrote: post #575
anonymars wrote: post #400

Earlier quoted context omitted.

Yes, but that also doesn't get any energy back on descent, quite the opposite, that is "riding the brakes on your way down"

Well it's not all lost otherwise it'd be a stall spin accident caused by performing the maneuver with too little airspeed. And that's hard to do. It's a noisy maneuver, the air slamming against the fuselage makes itself heard. Once performed it's not easily forgotten. More dangerous than inadvertently spinning with too little airspeed is the possibility of shock cooling when relying on a forward slip for too much alt…

I thought this topic was about energy gained and lost during a go-around. If velocity was V and altitude was H before the go-around, and velocity and altitude are again the same V and H after the go-around, then it follows that all the potential energy that was accumulated during the go-around (from converting fuel into altitude) has been dissipated (lost). Otherwise V would be higher the second time.

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

#582

Post by lenerdenator »

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…

I mean, obviously, it's better to trust the pilots, but if they are jumping the line because "fuel low" when it's not low, well, they're not being very professional, are they?

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

#583

Post by howard941 »

anonymars wrote: post #581
howard941 wrote: post #575

Earlier quoted context omitted.

Well it's not all lost otherwise it'd be a stall spin accident caused by performing the maneuver with too little airspeed. And that's hard to do. It's a noisy maneuver, the air slamming against the fuselage makes itself heard. Once performed it's not easily forgotten. More dangerous than inadvertently spinning with too little airspeed is the possibility of shock cooling when relying on a forward slip for too much alt…

I thought this topic was about energy gained and lost during a go-around. If velocity was V and altitude was H before the go-around, and velocity and altitude are again the same V and H after the go-around, then it follows that all the potential energy that was accumulated during the go-around (from converting fuel into altitude) has been dissipated (lost). Otherwise V would be higher the second time.

The subtopic changed from energy gained during descents to descents in general

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

#584

Post by tamcap »

Reason077 wrote: post #559
tamcap wrote: post #528

Earlier quoted context omitted.

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…

> "no real mass produced passenger plane today can use that electricity for flight (thrust)" Such aircraft do exist. For example, the Pipistrel Velis Electro trainer. And more recently, the Rhyxeon RX4E became the first electric aircraft to be type-certified for commercial passenger operations. It's likely that we'll see many more electric fan aircraft in the coming years/decades, whether powered by batteries and/or…

> It has a cruise speed of about 200 km/h (\(124\) mph), a payload of \(350\) kg (\(770\) lbs), and a range of approximately 300 km (\(186\) miles)

While it’s a real plane, I think we can both agree this is more of a prototype than what the general public would consider to be a passenger plane.

Yes, energy recovery is possible. It’s not happening currently in commercial aviation.

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

#585

Post by ktallett »

kqr wrote: post #439
ktallett wrote: post #98

Earlier quoted context omitted.

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 max level, and it is three.

Well clearly that number should depend on distance to next airport and how much fuel is onboard. It isn't sensible to have a set number when other parameters change.

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

#586

Post by pjb88 »

I saw this plane out my window when it was landing at Prestwick. It was dark and windy about 60mph and I said to my wife "what's that in the sky". The airport is about 5 miles away, for some reason this one caught my eye - in the hundreds/thousands of planes that go by I've never said that before, don't know if it was pointed an odd direction but it appeared stationary. We thought it was like a star, but too bright. We looked it up on flight radar to see if it was a plane and it was the one that later came out.

I know this will not be relevant to anything but I thought it was a strange coincidence then I saw it on my hn feed.

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