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Screw rockets

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Rockets are very wasteful when operated in the lower atmosphere (up to, say, 100,000ft); this is even truer of single- stage rockets that must use the same rocket nozzle in air as they do in space.

Meanwhile, propellors and rotors are actually a fairly efficient way of generating thrust/lift in air, which is why helicopters work to some extent. So, just build the rocket with two huge rotor blades fixed to the body. Offset the thrust of the rocket engines very, very slightly so as to induce spin. Hey presto, your rocket will literally screw itself into the air, and you still get almost all of the direct rocket thrust besides.

At some point, it will be advisable to jettison the blades, preferably all at the same time.

MaxwellBuchanan, Jan 21 2019

Focke-Wulf Triebflügel https://en.wikipedi...lf_Triebfl%C3%BCgel
Never got off the drawing board, let alone the ground ... [8th of 7, Jan 21 2019]

Some cultures get all the fun... https://ca.video.se...81484b7&action=view
[2 fries shy of a happy meal, Jan 21 2019]

Like this... https://en.wikipedi.../wiki/Rotary_Rocket
The Roton. [neutrinos_shadow, Jan 21 2019]

Sceince rap https://youtu.be/SFs9VX4zv7g
not that great [not_morrison_rm, Jan 22 2019]

[link]






       As you should have expected, the Prior Art in this area belongs to the Nazis, and is the distinctive Focke-Wolf Triebflügel tailsitting VTOL fighter.   

       <link>
8th of 7, Jan 21 2019
  

       Ooh, you'll like this then. [link]   

       There was the Roton concept, which is like this. But you keep the rotor blades for landing.
It wasn't very good.
neutrinos_shadow, Jan 21 2019
  

       Re. third link: Bloody typical. Every time I invent something, some bastard goes and pre-empts me.   

       I'm beginning to wish I won't have made my time-machine plans available online.
MaxwellBuchanan, Jan 21 2019
  

       I'm thinking the astrodog will get dizzy.
RayfordSteele, Jan 21 2019
  

       Damn the torpedoes
Ian Tindale, Jan 22 2019
  

       The spinning rocket should be no problem, but a spinning fuel tank going through max Q probably not so easy.
bigsleep, Jan 22 2019
  

       Materials will only get stronger, fuel density will only get higher, peer reviewed science won't accept anything else.   

       I always wondered why a rocket tries to thrust a volume that is leaving at thrust speed rather than turning slightly to thrust against the more turbulent, and in my mind, harder expansion edge.
wjt, Jan 22 2019
  

       // I always wondered why a rocket tries to thrust a volume that is leaving at thrust speed rather than turning slightly to thrust against the more turbulent, and in my mind, harder expansion edge. //   

       That sounds like it could be an interesting theory, but unfortunately I don't have the background info to know what you're talking about. Could you further explain (or provide links explaining) what you mean by // thrust a volume that is leaving at thrust speed // and // expansion edge //
scad mientist, Jan 22 2019
  

       [wjt] is confusing a rocket - which works purely by momentum transfer - with a jet - which generates "pressure" at its outlet.   

       This is the reason that rockets work in vacuum, but turbojets don't (quite apart from the lack of air as a working fluid).
8th of 7, Jan 22 2019
  

       The other Thrust definition, To push or drive quickly and forcefully   

       The area between the ground and the edge of space has atmosphere. Which is more pushing out a ball or pushing on a ball that is pushing on a wall? It seems the rocket could use the atmosphere rather than fight it. Using only momentum transfer seems the ultimate in cavitation.
wjt, Jan 22 2019
  

       //Every time I invent something, some bastard goes and pre-empts me.// Never mind. You could always just invert your idea and invent the rocket powered corkscrew. No one has pre-empted that one. (oh wait - I just have!) Poor Max
xenzag, Jan 22 2019
  

       //rockets work in vacuum   

       I tried that once, set fire to the dust bag, they ain't cheap you know.   

       Reading further down the Rotary Rocket wiki I came across "A full size, 63 ft (19 m) tall, Atmospheric Test Vehicle (ATV) was built under contract by Scaled Composites"... and it rose to a shocking 75ft on the last go.   

       Now, if the ATV had been situated somewhere on Earth that is 74 foot from vacuum, they'd all be tootling around in gold-plated Rolls-Royces by now. It's the little details...   

       Anyway, I was looking for the Science:Rapping and der ain't one.
not_morrison_rm, Jan 22 2019
  

       //situated somewhere on Earth that is 74 foot from vacuum// How about 23 metres outside Milton Keynes?
MaxwellBuchanan, Jan 22 2019
  

       Is Milton Keynes named after John Milton or the famous baby bottle bleach brand?
xenzag, Jan 22 2019
  

       It's actually named for Milton Berle and Skandar Keynes.
MaxwellBuchanan, Jan 22 2019
  

       Odd, we had the suspicion that John Maynard Keynes was somehow involved; something to do with the ability of economists to instantly suck all the oxygen out of the atmosphere ...   

       // tried that once, set fire to the dust bag, they ain't cheap you know. //   

       Oh, we know.   

       Worse, if you try it with a Dyson, it melts, and the parts are ludicrously expensive.   

       // they'd all be tootling around in gold-plated Rolls-Royces by now. //   

       Strange as it may seem, Burt Rutan actually has things (many of which he designed) that are more fun than a gold-plated Rolls-Royce.
8th of 7, Jan 22 2019
  

       Taking the economist view, is there such a thing as a stoichiometric reaction specific impulse? Does it's numbers scale up with the measured macro specific impulse or is it a sum greater than parts kind of deal, impulse of an impulse?
wjt, Jan 22 2019
  

       Yeah. What have they ever done for us.
bigsleep, Jan 26 2019
  
      
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