Lighter/simpler turbo pump

Len wrote:

In the early 1960s, Rocketdyne considered a "pinwheel
rocket pump"--which sounds pretty close to what you are
suggesting. I always thought it was potentially a good
idea, but I don't think the Rocketdyne pinwheel got much
past the briefing chart (before viewgraphs) stage.



The original powerplant for the Northrop XP-79 flying-wing fighter was
to be the "Rotojet" rocket motor; it had a total of four combustion
chambers (two high thrust and two low thrust) mounted at slight angles
to the main part of the engine's thrust axis on a rotating assembly, so
that this multiple combustion chamber assembly would spin and power the
engine's turbopumps in the main stationary part of the engine via a
drive shaft. Trying to get the fuel and oxidizer (aniline and RFNA,
which were hypergolic) to the combustion chambers via rotary fuel supply
feeders proved impossible to accomplish safely, and the motor was
canceled and replace by two small turbojets on the XP-79B prototype.
The Rotojet was a classic example of being too clever for your own good
when it comes to nifty engineering ideas.
Northrop tried to pooh-pooh the idea that the aircraft, named the
"Flying Ram" was actually intended to ram enemy bombers in their tail
assembly to destroy them...until a piece of Northrop official company
artwork surfaced showing it doing exactly that.
Sure...ram a He-177 in the tail in a magnesium aircraft full of aniline
and RFNA...Northrop had managed to design something that made the Me-163
Komet look safe. :-D

Pat