Lessons Unlearned

In 2007 we tried to build a 4 engine Lox Ethanoal rocket. When we were done it had 39 valves and was just wayyyy too complicated to work reliably. My present 180 second fantasy goes back in that direction a tiny little bit. If youmake the following assumptions:

• Electrically driven peroxide and RP-1 pumps.


• Catalyst decomposition with lots of pressure drop for relability


• 1000 to 1200 PSI feed pressure


• 700–800 PSI chamber presure.


• Four engines.


• 80% of theoretical ISP.

Then what drops out is

• Off the shelf small aluminum frame hydralic pumps (Possibly with one section redone with stainless gears)


• Off the shelf  Pump motors,batteries and gearing from  high end 600 sized RC helicopters.


• Hover times of 240 seconds+ with payload.


• A rocket with two manually operated valves (Vent and drain)


• Tanks with a pressure safety factor >4 so humans can be near the presurized rocket.


• A rocket with no active valves. (All control is from the pump speed control)


• Precise Mixture control.


• Safety system is all electrical, power stops to motors and down it comes.

I’ve ordered a pump to evaluate its peroxide compatibility and life time running unlubricated.  The pump was only $72.