von Braun was asked to chair a committee to study the existing efforts and write up recommendations. They presented their report on 18 July 1958, starting with a criticism of how the US program had been mishandled to date and pointing out that the Soviet program was definitely ahead. It went on to describe five "generations" of rockets, starting with the early Vanguard, through the Juno, ICBMs like Atlas and Titan, clustered designs like the Saturn, and finally, the ultimate development, a cluster using the F-1 with of thrust. The report went on to outline a crewed exploration program using these rockets as they become available; using existing ICBMs a small four-man space station could be operational 1961, the clusters would support a crewed lunar landing in 1965-1966 and a larger 50-man space station by 1967, while the largest of the rockets would support large Moon expeditions in 1972, set up a permanent Moon base in 1973-1974, and launch crewed interplanetary trips in 1977.