Re: Plane crash at Biggin Hill.

Conor wrote:
In article <13v07doko4pvta9@xxxxxxxxxxxxxxxxxx>, says...

You must be mistaken - I've been told planes can't just drop out of the
sky from engine(s) failure.
Where have I said they can? What you have there is a direct quote from a pilot eye whiteness.

I was told in uk.r.d by countless people that a plane cannot just drop straight out of the sky if there was a power failure and that it would merely glide to the ground despite everything I've learned in Principles of Flight saying different.

I don't know where you got that from but it sounds dodgy. All aircraft are subject to four forces - lift, weight, drag and thrust. The thrust (whether from an IC engine or a turbine) opposes the drag and provides speed which helps the wing produce lift to carry the weight. In normal operation all these forces are in balance.

Of course gliders have no engine, so they get their equivalent of thrust from exchanging potential energy (i.e height) for kinetic energy (i.e. speed) and this also tells you how powered aeroplanes who suddenly suffer engine failure behave.

But there is a point in any flight where lack of thrust can have bad consequences - normally if this happens when the aeroplane is too close to the ground as appears to have happened to this one.

This is why when learning to fly you are always taught to look for alternative landing places until you get enough height to glide back round the circuit and land back in the case that the engine(s) fail. Take off is a very critical time for engines - on most aircraft this is when they are operating at or about full power, and therefore most likely to fail.

How much height you need depends on the type of aircraft. This can be a couple of hundred feet in a properly designed glider, or a few thousand feet for an aircraft with not very good low speed performance - I would guess the Cessna Citation (of which I've no experience) falls into this category since its probably optimised for high speed cruise.

Nightjar may wish to expand further on this.

--
John Wright

I feel like an insane person with the ability to mimic sanity
.

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