Re: SPACE: Roton in New Scientist

Michael Lorrey (
Fri, 07 Aug 1998 13:42:26 -0400

Michelle Jones wrote:

> wrote:
> > Gary Hudson is a pretty smart guy; if he says he can do it, I think he has
> > a good chance of doing it. And, frankly, an 80% reduction over inflated
> > government launch costs shouldn't be that hard. Mark
> mark the reason i am having such difficulty with this concept is that the
> roton is a re-entry system. you still have to lift the thing into orbit
> somehow to reenter the atmosphere. the reentry system of modern
> government launchers is neither the cost driver nor the weight driver. spike

The roton rotor blades are also used for launching as well. The rocket engines are supposed to be on the tips of the rotors, and the centrifugal forces generated by the rocket propelled spin helps to feed the fuel to the motors, thus eliminating the weight of fuel pumps and reducing the mechanical complexity of the system (the highest maintenance parts of the space shuttle are the fuel pumps). There is also an efficiency gain here. Since the chemical reaction of the fuel propells the rotor around (gradually rotating to full forward propulsion beyond the atmosphere, kind of like how the V-22 Osprey rotates its wingtip motors) and the rotor is using the reaction mass in the atmosphere, you gain a bit of efficiency here. In propulsion, it is always more efficient to move a lot of mass a little, rather than a little mass a lot (those who think that ion/plasma type drives are efficient are only right in that they are MASS efficient, but definitely not energy efficient). Because of this setup, the roton can fire up its rotor-tip engines when it lands in order to maneuver around if it needs to for alternate landing sites, to counteract crosswinds, etc., which gives it a bit more maneuverability than a normal autogyro.

Mike Lorrey