On To The Six Grain

We have finally fired Trunnion, and it was an amazing success. Our first 8" composite motor has fired, and we couldn't be more excited to move on to our next project - a full length, 8" diameter, 6 bates-grain flight motor. Despite being on April Fool's day, the static firing of our 2 grain Trunnion motor went without any major surprises.This test-fire was not just an ordinary motor performance test. Firing Trunnion was a demonstration of USCRPL's own composite motor case technology, and luckily it was a demonstration of its feasibility and effectiveness. Everything went to plan - the integration of our equipment on site, the data-acquisition setup, the assembly of the motor and its hardware, and the actual firing.

The data we acquired looks great. The thrust curve looks beautiful (classic flat Bates-Grain profile), and within ~60lbs of our theoretical thrust calculations. The pressure and temperature data are also all within a safe range, and we believe that we are more than ready to move on to construction of our planned high thrust flight motor, which will be three times the length of this one. One note: The main difference between this firing of Trunnion and the one last November is the nozzle construction. The last design won't be flown because it was designed with a significant factor of safety and is therefore much too heavy.

On to photos of the launch!

A nice view of one of the bates grains


Jordan attaches an insulator plate to the top of the grain

This is Alec and Mitch's baby. The carrier is all steel, and you can see it heat up white-hot in the video below

Fitting the liner with the grains into the motor case

Ian Whittinghill and Dave Crisalli inspect the assembly of the motor

Joe readies the data acquisition hardware. We had three thermocouples, one pressure sensor, and one strain gauge


Assembling the thrust stand (informally known as "Jordan's Last Stand")

Mach diamonds!