Back in April at the MTA, we witnessed a static fire of a micrograin “tractor” rocket. A lot of the I_sp loss of a micrograin occurs since the burning fuel basically falls out the back end of the motor, producing the fantastic exhaust plume that makes micrograins so seductive. The idea of the “tractor” was to force most of the combustion to occur inside of the chamber by locating the nozzle at the top end of the motor. Unfortunately, this flight vehicle experienced the fate of many micrograin rockets:

Oops.

What good is it having a blog without some pretty pictures?
I really need to get out and fly again… haven’t tried since BALLS, I think. Oh well. Here’s some old ones… like here, when things go right… a 98mm N motor with 42″ of propellant (82% solids, 6% Al with a dash of CuO) pushing my school’s rocket “Del Carbon”, made using the techniques I talked about in the composite layups post (yay shameless trackback #2…)

Here’s when things go wrong. We (me and the school group) tried to do a carbon fiber cased O motor, but we had a “peel failure” between the casing layers. The case delaminated and allowed the forward bulkhead to fly out on pressure-up, absolutely torching Les Derkovitz’s rail. We’re still sorry, Les:

Whew. Glad the Flickr integration works well too.