Tonight while getting ready to test an MHD unit the rocket motor unexpectedly fired. Fortunately our test procedure calls for the battery to the motor to be hooked up only after the operator is clear. I’m not sure what caused it. A short in the ignition should only be able to result in not being able to fire. Tomorrow the troubleshooting begins.
The ceramic plates cracked on the last unit and the whole thing collapsed in on itself. We replaced the upper ceramic plate with a carbon fiber one. We also changed the motor mount to make it easier to assemble and disassemble. The carbon plate allows the magnets to be a little closed together. I was hoping to juice a little more power out. On the plus side the new unit held together. On the minus side the motor fired before the data logger began recording so no data. At least I was really awake for the drive home!
