One of the most remarkable of the Wunderwaffen (wonder weapons) produced by the Nazi Germany during World War II, the Messerschmitt Me 163 Komet holds the distinction of being the first and only tailless rocket-powered interceptor to see operational service. Like the other advanced weapons fielded by Germany during the final year of World War II, the Me 163 had little actual effect on the outcome of the war. Considering the conditions under which it was developed and deployed, however, the Me 163 can be rightly considered a significant technological accomplishment.
The concept for the Komet originated during the late thirties, when rocket propulsion for aircraft became increasingly attractive to a number of air planners in Nazi Germany. Although rockets potentially offered astounding performance advantages for an interceptor, their high fuel consumption posed seemingly insurmountable design difficulties. In spite of this, the Reichsluftfahrtministerium or RLM (Reich Air Ministry) supported the work of rocket engine designer Hellmuth Walter, issuing a contract in 1936 for the development of an 882 lb. thrust motor designated the R I-203. The engine was to be fueled by a mixture of T-Stoff (80 percent hydrogen peroxide with oxyquinoline or phosphate as a stabilizer and 20 percent water) and Z-Stoff (an aqueous solution of calcium permanganate) and intended to power the Heinkel He 176 aircraft then under development. Because the He 176, which had been designed solely as a high-speed aircraft with no military potential, the RLM ordered the Deutsches Forschungsinsitut für Segelflug (German Research Institute for Gliding Flight or DFS) to produce a second prototype of the DFS 39, a tailless aircraft designed by Dr. Alexander Lippisch. It was also to be a rocket-powered design under a top-secret program designated Project X. DFS was to build the aircraft's wings while Heinkel, which was already working on the He 176, was to manufacture the rest of the airframe. It soon became apparent to Lippisch, however, that the DFS 39's wingtip-mounted rudders would likely cause unacceptable flutter and that a central fin and rudder would offer better control. It was replaced by a new design, designated the DFS 194, with a single large vertical stabilizer mounted on the fuselage. Like the DFS 39, it was initially intended only to be a conventionally powered flying test bed for later rocket-powered designs.
Difficulties arising from the division of work between DFS and Heinkel and the secrecy surrounding the project led Lippisch to request that he be allowed to leave DFS and join Messerschmitt AG. The RLM granted his request on January 2, 1939, and shortly after Lippisch, his design team, and the partially completed DFS 194 arrived at the Messerschmitt works in Augsburg, it was decided to adopt rocket power for the aircraft. The airframe was completed at the Messerschmitt works in Augsburg and shipped to Pennemünde West early in 1940 for installation of a Walter R I-203. Flight-testing revealed that despite the unreliability its motor, the aircraft had excellent performance characteristics, reaching a speed of 342 mph in level flight during one test.
The move to Messerschmitt brought a change in the program's designation to Me 163. The success of the DFS 194 spurred development of the first prototype Me 163, designated the Me 163 V1, which was completed during early 1941. Flight testing commenced in the spring of 1941, comprising a series of unpowered flights before the Me 163 V1 was shipped to Peenemünde West for installation of a 1,653 lb. thrust Walter RII-203 rocket motor and its first powered flights. Despite a series of accidents and explosions involving the unreliable motor, on October 2, 1941, the Me 163 V1 set a new world speed record of 1,004.5 kph (623.8 mph). Impressed by the aircraft's performance, the RLM instructed Lippisch was to design an improved version of the Me 163 around a more powerful rocket motor under development by Walter. The new design, designated Me 163 B, was to be an operational interceptor and represented an almost complete redesign of the aircraft. Its landing gear remained similar to the earlier design, employing a wheeled trolley that was jettisoned after takeoff and an extendable skid for landing. Additional prototypes based on the Me 163 V1 configuration were designated Me 163 A.
The first Me 163 B prototype, the Me 163 V3, was completed in April 1942, but it was not until early fall that the first Walter 109-509A motors were ready for installation. The new motor used a more volatile fuel mixture of T-Stoff (80 percent hydrogen peroxide and 20 percent water) and C-Stoff (hydrazine hydrate, methyl alcohol, and water), which provided a maximum thrust of 1,500 kg (3,300 lb.). Unlike the earlier cold principle motor which directed all of the oxygen and water vapor produced by the decomposition of the hydrogen peroxide out of the engine's nozzle, the new motor employed a hot system in which the oxygen was ignited for additional thrust and better fuel efficiency. Flight testing of the first series of Me 163 B-0 preproduction aircraft proceeded through 1942 and demonstrated the dangers of the Me 163's unproven propulsion system. As fuel passed through the Walter motor's pumps, areas of vacuum sometimes formed in the liquid. This cavitation often caused a catastrophic explosion when the motor was started. Once in the air, the aircraft's climb rate proved remarkable, but compressibility problems limited its safe speed in a dive to below Mach 0.82. The Komet's landing gear also proved troublesome, with numerous pilots suffering back injuries as a result of the skid failing to extend properly or failing upon touchdown. Even when the skid operated properly, landings were always without power and at high speed, requiring the utmost care on the part of the pilot to prevent the aircraft from overturning on soft ground. Such mishaps often led to an explosion or the pilot being severely burned by leaking fuel.
Despite the problems encountered during testing, plans proceeded during 1943 to equip the first operational units with the operational version of the Komet, designated the Me 163 B-1a. Production began at dispersed facilities by the Klemm concern, but was later transferred to Junkers as the result of quality control problems. An operational training unit, Erprobungskommando 16 or EK 16 was formed during July 1943 at Pennemünde West, but moved to Bad Zwischenahn before the first group of pilot trainees arrived as the result of allied bombing of Pennemünde. The unit finally received its first group of 30 pilot trainees in the fall of 1943. By May 1944, organization of Jagdgeschwader 400 or JG 400, the first operational Me 163 wing, began in earnest with the formation of the unit's first group (I./JG 400) under the command of Hauptmann Wolfgang Späte. Späte planned to deploy Me 163s from a string of bases, each close enough that the short range of the Me 163 overlapped. The plan was never realized, owing in part to the special facilities needed for the aircraft. Instead, I./JG 400 was to provide protection for the synthetic oil refineries at Leuna, some 90 km (55 miles) from its base at Brandis. Two additional Me 163 groups, II. And III./JG 400 were formed before the end of the war, but saw limited combat.
The unit made its first interception of Allied bombers on August 16, 1944 without success. Early combat experiences demonstrated a number of problems that prevented the Me 163 from ever becoming an effective weapon. Although the aircraft's two MK 108 30mm cannons were capable of downing a four-engine bomber with only three or four hits, the Komet's high speed, coupled with the cannons' slow rate of fire and short range made effective gunnery nearly impossible against the slow moving bombers. As a result, Me 163 pilots recorded a total of only nine kills. Although capable of reaching its service ceiling of 12,100 m (39,690 ft) in just under three-and-a-half minutes, the Me 163 carried only enough fuel for eight minutes of powered flight. After one or two firing passes, the pilot had to glide back to base with no means of escaping Allied escort fighters. In response to pilots' combat reports, alternative weapons, including vertically firing 50mm cannons triggered by a photocell as the Me 163 passed through a bomber's shadow were tested but not produced in quantity. An improved variant of the aircraft with a greater endurance and a tricycle landing gear, designated the Me 163 C, was also produced in small numbers before the war's end, but was not flown operationally.
The operational history of the National Air and Space Museum's Me 163 B-1a, Werk-Nummer (serial number) 191301, remains obscure. One of five Me 163s brought to the United States after the war, it arrived at Freeman Field, Indiana, during the summer of 1945. There it received the foreign equipment code FE-500. On April 12, 1946, it was flown aboard a cargo aircraft to the U.S. Army Air Forces facility at Muroc dry lake in California for flight testing. Testing began there on May 3, 1946 in the presence of Dr. Alexander Lippisch and involved towing the unfueled Komet behind a B-29 to an altitude of 9,000 to 10,500 m (30,000 to 35,000 ft) before it was released for a glide back to earth under the control of test pilot Major Gus Lundquist. Powered tests were planned, but not carried out after delamination of the aircraft's wooden wings was discovered. It was then stored at Norton AFB, California until 1954, when it was transferred to the Smithsonian Institution. The aircraft remained on display in an unrestored condition at the museum's Paul E. Garber Restoration and Storage Facility in Suitland, Maryland, until 1996, when it was lent to the Mighty Eighth Air Force Heritage Museum in Savannah, Georgia. It is currently displayed at the Museum's Steven F. Udvar-Hazy Center in Chantilly, VA.