Space Exploration Timeline

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RTV-G-4 Bumper rocket

May 13, 1948 – Jul 29, 1950

The RTV-G-4 Bumper was a sounding rocket built by the United States. A combination of the German V-2 rocket and the WAC Corporal sounding rocket, it was used to study problems pertaining to two-stage high-speed rockets. The Bumper program launched eight rockets between May 13, 1948 and July 29, 1950. The first six flights were conducted at the White Sands Missile Range; the seventh launch, Bumper 8 on July 24, 1950, was the first rocket launched from Cape Canaveral.

https://wikipedia.org/wiki/RTV-G-4_Bumper

Includes events (3):
May 13, 1948
RTV-G-4 Bumper first flight
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Feb 24, 1949
First two-stage liquid-fueled rocket sets a record altitude (WAC Corporal missile mounted onto a V-2 rocket)
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Jul 29, 1950
RTV-G-4 Bumper last flight
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