This week we tested the 2L bottles we use for the Acceleron III rocket. After the failure a couple of weeks back we wanted to see what these particular bottles can hold. We also did a test with a coupling as we suspect it was a bottle that failed near a coupling.
The burst pressures were at 165psi which is about what we found with other 2L bottles tested earlier. We also pressurised one to 130psi and held it there for 3 minutes. After three minutes we started increasing the pressure and it burst at around 150psi. Therefore we will drop the operational pressure of the rocket to 110psi until we start reinforcing the bottles.
We are now in the process of getting more bottles since 5 of them were tested to destruction and can't be used of course. We need about 8 more bottles which we should have this week.
We also completed the large parachute for the rocket yesterday. The parachute needs to be fairly big as the booster weighs around 2Kg dry.