I'd be pretty uncomfortable with this, especially on Skidmark motors. On all 4 of the CATOs I saw, the rocket got several feet off the pad and then blew out, throwing flame forward while falling to the ground. If that was a sparky, it'd be throwing sparks and flames in a random direction, likely torching anything nearby. I guess if you launched on salt flats or a frozen lake where there's nothing flammable for hundreds of yards around and people are well back. Even so, sounds pretty sketchy.
We had enough distance between the rocket and the people. The motor burnt through immedietly after liftoff, so it happened only a few meters from the ground.
But we should make a distinction between failure-modes: The 4 abovementioned and my example (3x H123SK) was a burnthrough of the delaygrain, no liner failure or something like that.
In these motors, the delay grain seems to burn faster than the propellant itself, and we found here that they all come from a few batches from a small time period.
I saw a lot of CTI motors, and very seldom a failure, they are in general very safe to handle for me.
But on this event we had 3 failures in a row, all the same motor, all the same failure, all the same batch.
The H225 has the same failure, also in a row, a batch made 9 days later than our motors. Could be possible, that they all used the same delay grain mix.
That is not normal, and may show a general fault in these motors from these batches, or more precise, a fault in the delay mixture in these reloads.
Maybe they used normal propellant for that instead of a slow burning mix. **** happens.
I personally would not use a motor from september/october 2015 until this is investigated.
Louis
