Bumper rocket number 5 launches from White Sands Proving Ground, New Mexico on 24 February 1949. It achieved an altitude of 250 miles, a record at the time.
Staged rockets are composed of separate rocket bodies—each with its own engines and fuel supply—stacked in series and fired in sequence to progressively gain speed, escape the Earth’s gravity and maneuver into final orbit. The first stage is the most powerful by far, lifting the rocket off the launchpad and approaching escape velocity before burning out, falling away, and allowing the secondary stage to ignite. The third and final stage finesses the payload to its target altitude. The Army’s first multi-stage rocket was codenamed Bumper. Bumper was a two-stage model that consisted of an Army Corporal rocket tucked inside a V-2 shell. The Army tested eight Bumper rockets, six at White Sands Proving Ground in New Mexico and two at Cape Canaveral. The first fully loaded Bumper, launched in 1949, achieved the highest velocity and altitude of any manmade object at that time. The Army’s innovations with the Bumper led to the simply named Redstone rocket, the first true V-2 successor. The initial Redstone model, the PGM-11, became the Army's workhorse medium-range ballistic missile. Some experimental models were capable of traveling more than 3300 miles downrange.