Messerschmitt Me-262

The Messerschmitt Me 262 Schwalbe (German: "Swallow") was the world's first operational turbojet fighter aircraft. It was produced in World War II and saw action starting in 1944 as a multi-role fighter / bomber / reconnaissance / interceptor warplane for the Luftwaffe. It was officially named Schwalbe because the swallow, when in a dive, is one of the fastest birds known.[citation needed] German pilots nicknamed it the "Turbo," while the Allies called it the "Stormbird." The Me 262 had a negligible impact on the course of the war, with 509 claimed Allied kills[3], (although higher claims are sometimes made[4]) for more than 100 Me 262 losses.

Design and development
Me 262A on display at the Deutsches Museum.
Me 262A on display at the Deutsches Museum.

The Me 262 was already being developed as Projekt P.1065 before the start of World War II. Plans were first drawn up in April 1939, and the original design was very similar to the plane that eventually entered service. The progression of the original design into service was delayed greatly by technical issues involving the new jet engines. Funding for the jet program was also initially lacking as many high-ranking officials thought that the war could easily be won with conventional aircraft. Adolf Hitler had envisioned that the Me 262 be produced not as a defensive interceptor, but in an offensive ground attack/bomber role. His edict resulted in the Sturmvogel (Stormbird) variant. Although debatable, it is generally agreed that Hitler's interference was not a major reason for delay in bringing the Swallow into operation.[5][6]

The aircraft was originally designed with a tail wheel undercarriage and the first four prototypes (Me 262 V1-V4) were built with this configuration, but it was discovered on an early test run that the engines and wings "blanked" the stabilizers, giving almost no control on the ground. Changing to a tricycle undercarriage arrangement, initially as a fixed undercarriage on the fifth prototype aircraft, then a fully retractable one on the sixth and succeeding prototypes, corrected this problem.

Although it is often stated that the Me 262 is a "swept wing" design, the production Me 262 had a leading edge sweep of only 18.5°. This was done primarily to properly position the center of lift relative to the centre of mass and not for the aerodynamic benefit of increasing the critical Mach number of the wing. The sweep was too slight to achieve any significant advantage.[7] This happened after the initial design of the aircraft, when the engines proved to be heavier than originally expected. On 1 March 1940, instead of moving the wing forward on its mount, the outer wing was positioned slightly backwards to the same end. The middle section of the wing remained unswept.[8]. Based on data from the AVA Göttingen and windtunnel results, the middle section was later swept.

The first test flights began on 18 April 1941, but since the BMW 003 turbojets were not ready for fitting, a conventional Junkers Jumo 210 engine was mounted in the nose, driving a propeller, to test the Me 262 V1 airframe. When the BMW 003 engines were finally installed the Jumo was retained for safety which proved wise as both 003s failed during the first flight and the pilot had to land using the nose mounted engine alone.

The V3 third prototype airframe became a true "jet" when it flew on 18 July 1942 in Leipheim near Günzburg, Germany, piloted by Fritz Wendel. This was almost nine months ahead of the British Gloster Meteor's first flight on 5 March 1943. The 003 engines, which were proving unreliable, were replaced by the newly available Junkers Jumo 004. Test flights continued over the next year but the engines continued to be unreliable. Airframe modifications were complete by 1942, but hampered by the lack of engines, serial production did not begin until 1944. This delay in engine availability was in part due to the shortage of strategic materials, especially metals and alloys that could handle the extreme temperatures produced by the jet engine. Even when the engines were completed they had an expected operational lifetime of approximately 50 hours, however in the real world most 004s' lifetimes were 12 hours. A pilot familiar with the Me 262 and its engines could expect approximately 20 to 25 hours of life from the 004s. The swap out of 004s was listed as a job able to be done in three hours, but changeouts typically took eight to nine hours due to poorly made parts and inadequate training of ground crews.

Turbojet engines have less thrust at low speed than propellers and as a result, low-speed acceleration is relatively poor. It was more noticeable for the Me 262 as early jet engines (before the invention of afterburners) responded slowly to throttle changes. The introduction of a primitive autothrottle late in the war only helped slightly. Conversely, the higher power of jet engines at higher speeds meant the Me 262 enjoyed a much higher climb speed. Used tactically, this gave the jet fighter an even greater speed advantage in climb rate than level flight at top speed.

With one engine out, the Me 262 still flew well, with speeds of 280 to 310 mph (450 km/h to 500 km/h), but pilots were warned never to fly slower than 300 km/h (186 mph) on one engine, as the asymmetical thrust would cause serious problems below that speed.

Operationally, the Me 262 had an endurance of 60 to 90 minutes.