After the problems that developed during the MR-2 mission carrying the chimpanzee Ham, it was apparent that the Redstone needed further development before it could be trusted to carry a human passenger.
Nakon problema koji su nastali tijekom misije MR-2 koja je nosila čimpanzu Hama, bilo je očito da je Redstone trebao daljni razvoj prije nego mu se mogao povjeriti ljudski putnik.