AKA: RTV-G-10;RV-A-10;SSM-A-13;SSM-G-13;W-7. Status: Retired 1953. First Launch: 1947-05-30. Last Launch: 1953-03-25. Number: 8 . Thrust: 142.00 kN (31,922 lbf). Gross mass: 3,530 kg (7,780 lb). Unfuelled mass: 800 kg (1,760 lb). Burn time: 30 s. Height: 6.17 m (20.24 ft). Diameter: 0.79 m (2.59 ft). Span: 2.41 m (7.90 ft). Apogee: 58 km (36 mi).
Hermes A-2 began as a 1947 concept for a wingless surface-to-surface derivative of the Hermes A-1, itself an American version of the German Wasserfall surface-to-air missile. By 1948 it was decided to start with a clean sheet of paper design, replacing the liquid propellants of the Wasserfall with a more tactically appropriate solid rocket motor. This low-cost single-stage missile would have a range of 120 km / 75 miles when carrying a nuclear warhead. Thiokol began development of the solid propellant motor in 1950. The production tactical missile would be armed with a 40 kT W-7 nuclear fission warhead. The Hermes project was cancelled in October 1952 and further development of the missile was assigned to the Jet Propulsion Laboratory. Thiokol's success in development of the solid rocket motor led to flight tests of the unguided RV-A-10 test vehicle in the rundown after the program cancellation. Four were flown successfully in February-March 1953.
Maximum range: 109 km (67 mi). Number Standard Warheads: 1. Standard warhead: W-7. Warhead yield: 40 KT. Boost Propulsion: Solid.
Historical Essay © Andreas Parsch
The original Hermes A-2 was a wingless surface-to-surface derivative of the Hermes A-1, but this project died early in the planning stage around 1947. The A-2 designator was revived in 1948, when it was assigned to a proposed low-cost short-range (120 km (75 miles)) surface-to-surface missile to be powered by a solid-propellant rocket motor. Because large solid rocket motors were essentially an unexplored field at that time, the Hermes A-2 project's initial focus was on the RV-A-10 propulsion test vehicle (most probably designated RTV-G-10 before mid-1951; see note (2) on designation table below). However, a tactical missile (to be armed with a 40 kT W-7 nuclear fission warhead) was also projected as SSM-G-13 (SSM-A-13 after mid-1951).
In 1950, Thiokol began the development of the United States' first large solid-fueled rocket motor. After numerous tests with subscale motors and static firings, the first flight of the RV-A-10 occurred in February 1953. It was successful and was followed by three more successful tests in March that year, which ended the program. The RV-A-10 was a completely unguided rocket, but it validated the concept of solid-fuel propulsion for large missiles. However, the tactical XSSM-A-13 Hermes A-2 had already been cancelled in October 1952, and the development of a solid-fueled short-range ballistic missile was assigned by the Army to the JPL (Jet Propulsion Laboratory), leading to the SSM-A-27-MGM-29 Sergeant.
Hermes B-1 impacts a graveyard 18.5 km south of Juarez, Mexico on its first test flight. This and the out-of-range V-2 impact on 15 May resulted in new safety measures at WSPG. 'We were the first German unit to not only infiltrate the United States, but to attack Mexico from US soil'. This vehicle was deeply classified at the time. Hermes experiments were conducted with modified V-2 rockets to test the configuration of a ramjet propulsion system. Four Hermes B-1 rockets were flown from Complex 33, none of which were noted in the contemporary records.