Yesterday, I heard the sound of a helicopter nearby, but with a loud rattle as well as the normal noises. It flew past, quite high and fast. It was civilian. I hope it managed to reach somewhere safe, although we are in the country, so there are plenty of fields around, but I have never heard this kind of noise coming from a flying machine of any kind, let alone one that needs all its parts in perfect order. There were no reports on the TV news of crashed helicopters, I am glad to say.
OT: Rattling helicopter
Jul 31, 2020
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slap
Not to mention that the rotor blades have to remain in sync or they truncate each other.
Quite - that is pretty much the "Why?" loss of single rotor is unsurvivable.
Well I do know that any helicopter on the route over me has to be a twin. I think otherwise they have to fly over the Thames. Brian
Yep, twin engined over London, think the same applies to other large built up areas as well. Single engined helicopters not allowed or they have to be high enough to be able to gyro to surrounding open space.
Blade slap is much more of a whump-wmump-whump (5Hz?)noise than a rattle
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or to the river.
no soup for me...come back one year!
Can't think of a suitable river in Birmingham...
er no, they are in slightly different planes.
I was pointing our that a river makes a suitable emergency site.
Indeed. I would imaging that the blade pitch rather than speed would be the way that load adjustments are made.
Tim
A lot better than the roof of a pub, that?s for sure. Twin engines didn?t do much to stop the Clutha pub crash.
Tim
In the Chinook the Engines drive a common shaft which is connected to a whoopedo gearbox that ensures the rotors are synced
Wasn't that a fuel problem so both engines went quiet ? It wouldn't have made any difference if the helicopter had one or twenty engines.
Quite. Having ignored the warnings it was too late to go anywhere but down once it went bad.
True, but there is quite a lot of flex. IIRC once you lose synchronisation and things go a bit dynamic they can collide.
But if we follow the earlier point, a helicopter should have dual fuel syst ems, and they should be filled up separately (e.g. from different bunkers).
IIRC there was significant diversity in the fuel systems, but the pilot failed to operate the valves correctly. Colin will probably be along to explain it properly in a bit. (Maybe I mean redundancy rather than diversity). It didn't go as far as separate bunkers.
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