RTV-A-2 Hiroc

The RTV-A-2 Hiroc (High-altitude Rocket) was the United States' first attempt at an intercontinental ballistic missile (ICBM). In 1946, Consolidated-Vultee was given an Army Air Forces research contract and began design and development of the MX-774, which led to Convair's development of the Atlas ICBM. Although the MX-774 itself was cancelled, three prototype launch vehicles were built, designated RTV-A-2. The three rockets were launched in July, September, and December of 1948, all three launches being considered partial successes.