Hs-117 Schmetterling
Hs 117 Schmetterling
Of all the experimental German anti-aircraft missiles of World War II, the Hs 117 Schmetterling (originally designated the Hs 297) came closest to deployment. Mass production was ordered in December 1944, with deployment to begin in March 1945, but the plans were quite unrealistic, as was typical of the desperation programs of the last year of the Third Reich. The Schmetterling had its origin in 1941, when Prof. Dr. Herbert Wagner, the talented missile designer also responsible for the Hs 293 air-to-ground missile mostly used against ships, proposed a number of anti-aircraft projects. It was not until early 1943 that the Air Ministry issued the contract to Henschel Aircraft. The Hs 117 was fueled by a combination of nitric acid and Tonka, a mixed hydrocarbon fuel, and was boosted by two solid-fuel Schmidding rocket units, one each above and below on the missile. Guidance was by radio-control from an operator with a telescopic sight and joy-stick. The boosters are missing from the Museum's artifact, which was acquired from the U.S. Army Ordnance Museum at Aberdeen, Maryland, in 1988. Also missing is the warhead cone.
Construction:
The missile is aircraft-shaped with sweptback wings and cruciform tail, and has an asymmetrical nose with warhead extension on one side and a shorter extension on the other with a wind-driven generator propeller. The missile does not have regular control surfaces, but instead uses spoilers known as "Wagner bars" on the trailing edges of the wings and tailplane.
Length: 429 cm (14 ft. 1 in)(with warhead)
Diameter of fuselage: 35 cm (1 ft 1.75 in.)
Wingspan: 200 cm (6 ft 6.75 in.)
Weight, loaded: 420 kg (924 lb.)
Explosive wt.: 100 kg (220 lbs.)
Maximum speed: Mach 0.77
Range: 32km (20 mi.) with a ceiling of 10,000 m (32,800 ft.)
History:
Beginning in May 1944, 59 experimental launchings were made at Karlshagen, near Peenemuende. The Hs 117 normally used the BMW 109-558 rocket motor of 375 kg (825 lbs.) thrust for 33 seconds which fell to 60 kg (132 lbs.) over the last 24 seconds. The propellants were R-Stoff or Tonka, a mixed hydrocarbon fuel, and nitric acid. The propellants were fed into the combustion chamber by gaseous pressure and were hypergolic, or self-igniting. The two Schmidding 109-553 solid-fuel boosters weighed 170 kg (374 lb.) total, and produced 1,750 kg (3,850 lbs.) thrust each for four seconds.
There were several variants, including the the Hs 117H, the only known air-launched version. Designed for use from the Do 217, Ju 188, and Ju 388 aircraft, the Hs 117H had a truncated top tailfin and no boosters. Twenty-one flight tests were conducted from a Do 217, with only 15 being satisfactory. Development of the Hs 117-H ended in February, 1945. A standard Revi reflector sight was to be used for sighting the missile, while guidance was accomplished with conventional radio-link and line-of-sight by the pilot of the carrier plane. There were plans to install a homing device and proximity fuse in the missile, but this never materialized and detonations were normally activated by a radio signal. The Hs 117-H was designed to attack an enemy aircraft up to 5,000 m (16,400 ft) above the carrier aircraft.
References:
Gunston, Bill. The Illustrated Encyclopedia of the World's Rockets & Missiles (New York: Crescent Books, 1979), 148-149.
Hogg, I.V. German Secret Weapons of World War 2 (New York: Arco Publishing Co, 1970), 22-23.
Ley, Willy. Rockets, Missiles, and Space Travel (New York: The Viking Press, 1959), 225.
Ordway, Frederick I., III, and Ronald C. Wakeford, International Missile and Spacecraft Guide (New York: McGraw-Hill, 1960), 93-94, 133.
Smith, J.R., and Antony L. Kay, German Aircraft of the Second World War (London: Putnam, 1972), 688-691
http://www.nasm.si.edu/nasm/dsh/artifacts/RM-Hs117.htm