Comment Re:Did it really go ok? (Score 1) 383
"They need a clean, non-rotational separation before the second stage engine fires and can fully stabilize the flight path"
There is no such thing as a clean, non-rotational separation during a staging event. ALL vehicle I have ever worked on have rather dramatic forces, both linear and rotational, acting on both stages during a sep. Some of the cleanest are using linear shape charges to explosively cut the metal holding the stages together, but other systems such as V-Bands and pneumatic pistons have all been tried and have their own problems. And even if the sep systems doesn't impart energy, there is always the aero load. These birds are typically unstable during a sep. Think heavy fuel, located at rear of vehicle - wrong end. It was always a race to warm up the engines (about 0.5 to 2 seconds) and slew the TVC (have to wait to clear the interstage) and catch the vehicle before it tumbled.
And yes, I am a rocket scientist.