What kind of redundancy will the Spacecub have? How will you handle an engine out on landing?
The Spacecub is designed to have three to five (not yet finalized) engines. The rocket engines we are most interested in are the verniers from the Russian RD-107 or RD-108 engines. These engines have been around since the days of Sputnik and have established a simply incredible reliability. Other engines, mostly of Russian make, are also under consideration. In all cases, the ability to make a safe landing, at any point in the flight, should one engine fail, is a major design criterion. In the landing phase, the rocket has shed enough mass that any one engine is sufficient for landing. Control systems and electronics will be fully redundant, with nice, simple, foolproof mechanical switches for shifting from main to backup systems. Three computers, two GPS receivers, and two inertial platforms will give redundancy in navigation. Even primary structural member have redundancy. The three pressurized propellant tanks carry fuselage loads. Each one is sized, individually, to carry the entir
