This is a little outside the box, and feel free to tell me that I'm all wet.
I know well the reason that direct staging doesn't work with composites, and since it doesn't there's no reason for SU composites to come as -0 booster engines. But can a composite's ejection charge light a BP motor? Use the shortest delay available and have a little coast time before lighting a BP sustainer. Has this been tried? Does it work?
Then there's the other side of the coin. Would it be allowed to place a fast burning, high temperature fuse in a composite motor, such that the ignition (or ejection) charge below lights the fuse, which burns all the way up the core and lights the motor. I don't know if a suitable fuse exists, but I don't see why one couldn't. If one does, would there be any reason not to use it? Has this been tried? Does it work?
I know well the reason that direct staging doesn't work with composites, and since it doesn't there's no reason for SU composites to come as -0 booster engines. But can a composite's ejection charge light a BP motor? Use the shortest delay available and have a little coast time before lighting a BP sustainer. Has this been tried? Does it work?
Then there's the other side of the coin. Would it be allowed to place a fast burning, high temperature fuse in a composite motor, such that the ignition (or ejection) charge below lights the fuse, which burns all the way up the core and lights the motor. I don't know if a suitable fuse exists, but I don't see why one couldn't. If one does, would there be any reason not to use it? Has this been tried? Does it work?