
Why did the half-plane, half-helicopter not work? - jayflux
http://www.bbc.co.uk/news/magazine-35521040
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Melkman
Hmm, I'd say that V22 Osprey does work. It's still a compromise and a full
heli or full plane is better suited for most tasks but a hybrid does have its
use.

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johnjackamend
Eh. The total cost of its program ($35.6 billion) almost came to exactly $1
billion per death incurred by accidents during its testing from 1991-2000(36
fatalities). All that money and life spent on a somewhat functional newly
minted freedom boner.

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yongjik
I don't think "death per budget" is a meaningful metric, unless talking about
weapons or serial killers. You can't just take two numbers we want to
minimize, divide one by another, and claim significance.

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rbanffy
Multiplying them would be more meaningful.

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curtis
Another tip jet helicopter was the Sud-Ouest Djinn [1] from the 1950s. This
design was somewhat successful, with 178 units being built. Unlike other tip
jet designs, the Djinn used a fixed gas turbine to drive an air-compressor,
and the blades were simply powered by compressed-air tip jets. Since tip jet
driven rotors don't generate a lot of torque, the Djinn didn't have a tail
rotor.

[1] [https://en.wikipedia.org/wiki/Sud-
Ouest_Djinn](https://en.wikipedia.org/wiki/Sud-Ouest_Djinn)

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sandworm101
Too big and too complex. Just like the Osprey.

But Canadair has it all figured out. The CL-84 was a tilt-rotor, tilt-wing
aircraft that was landing troops on US carriers 40 years ahead of the Osprey.
It probably had 1/100th the part count.

[https://en.wikipedia.org/wiki/Canadair_CL-84](https://en.wikipedia.org/wiki/Canadair_CL-84)

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WalterBright
Helicopters are expensive - high fuel consumption, high maintenance. They're
also inherently much less safe than an airplane. A helicopter is inherently
unstable (it wants to crash, whereas an airplane wants to fly), and losing a
rotor blade means everyone dies (hence the high maintenance costs).

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detaro
What's the state of the art in active anti-noise technology for helicopters?
I've read about that kind of thing a few times, but don't know what actual
numbers are.

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TheOtherHobbes
It would be hard to anti-noise the Rotodyne because it literally had small jet
engines on the end of each rotor - which was why it so incredibly loud in
VTOL.

I can't find actual noise figures for it, but I suspect it wasn't all the much
louder than some modern jet liners. But jet liners land at out-of-city
airports, and the whole point of the Rotodyne was that it could land in the
middle of a city - and you're not going to get certification for that for a
plane that can be heard miles away.

I'd guess it was unbearably noisy inside the cabin too.

Here's a sales video, with vintage cheesy music and equally vintage British
accents:

[https://www.youtube.com/watch?v=u4Z1UnRZDyo](https://www.youtube.com/watch?v=u4Z1UnRZDyo)

