Jun 122013
In the late 1960s, prior to the Shuttle concept really taking off, the USAF funded studies of low cost boosters. One type that received considerable study was a two-stage pressure fed layout. This was vaguely similar to the earlier Aerojet Sea Dragon in that it would be a heavy and simple design, using shiplike construction and dense propellants. The nature of the first stage booster was such that recovery was anticipated. Propellants were hydrazine and nitric acid.