Wednesday, May 28, 2008

O to N two stage flight





This rocket
is one of the largest two stage amateur flights to date. Compare this to project tupelo, the two stage shadow aero kit (shock X2), and mostly to the project thunderbolt that used similar sized motors. Performance was huge, above mach 3 (something that the shadow aero web page claims for L to L kit, but that might be a stretch) and above 50,000 feet. I find this altitude a bit interesting, 50,000 feet seems a bit low if anything for a 2 stage flight to mach 3. You can see where the paint and even the composite skin were badly damaged by the friction created with the air stream above 2000 mph. Great work. Two stage rockets are far more efficient. Next step would be a P to N flight (CSXT attempt that failed to burn the upper stage) or even a Q to O motor. Either one of these would break 100,000 feet no problem. But clearly as this project shows... they need to have some serious heat protection. Either metal parts (generally the best idea despite the growing appeal of composites) or at least use some kind of high temp enamel.

3 comments:

DTH Rocket said...

This fascinates me. I can't wait until I'm old enough to be building these kinds of rockets...

Greg said...

Perhaps an ablative coating on the fins, similar to that which was used on the X-15A2 (the white X-15), might be in order.

R2K said...

Great point... My biggest concern is not failure of the rocket (these fins held up just fine) but reduced performance.

I said quickly that 50,000 feet seemed low... part of that might have been the huge extra drag these upper-stage fins added. I mean imagine a square inch or two of flapping fabric at mach 1.5 - 3? That probably was 50 - 100 lbs of drag right there! (Anyone want to do the math on this one and find out what PSI is as mach 3?)