Warplanes of Germany: Luftwaffe Messerschmitt Me 261

Messerschmitt Me 261

The Messerschmitt Me 261 (unofficiallynicknamed Adolfine) was a long-range reconnaissance aircraft designed in thelate 1930s. It looked like an enlarged version of the Messerschmitt Bf 110. Itwas not put into production; just three Me 261s were built and used primarilyfor testing and development purposes.

In 1937, Messerschmitt began Projekt P. 1064, a study for a long-rangereconnaissance aircraft, and took the design of the Bf 110 twin-engine heavyfighter (and derivative Bf 161 reconnaissance / Bf 162 light bomber projects)as its basis. The P. 1064 had a long, slim fuselage with two wing-mountedengines. The aircraft was planned from the outset as a record-breakingaircraft, but after becoming convinced that the aircraft was capable of takingthe world long-distance flight record, the German Air Ministry(Reichsluftfahrtministerium) approved the project and gave it the airframedesignation number of 8-261.

The intended goal of the project was for an example of the aircraft to carrythe Olympic flame from Garmisch-Partenkirchen, Germany (site of the 1936 WinterOlympics) to Tokyo, Japan for the 1940 Summer Olympics in what would be arecord-breaking nonstop flight[2] (5870 mi / 9445 km). The plan captured theimagination of Adolf Hitler at an early stage in its design and in tribute, theaircraft carried the unofficial name: Adolfine.

The Me 261 incorporated a number of features which were highly advanced for itsday. The single-spar all-metal wing was designed to serve as a fuel tank andits depth at the wing root was only slightly less than the height of thefuselage. The fuselage was of virtually rectangular section with space for fivecrew members, consisting of two pilots seated side-by-side with the radiooperator directly behind in the front compartment, while a navigator and aflight engineer were housed in the rear fuselage under a stepped, glazedstation.

Power came from four Daimler-Benz DB 601 engines, coupled together in pairs ina "power system" known as the DB 606, weighing 1.5 tonnes apiece anddebuting in February 1937. The DB 606 "power systems" were originallydeveloped for both the "single"-engined Heinkel He 119 high-speedreconnaissance aircraft, and the Heinkel He 177 strategic bomber, but the Me261's design housed the DB 606 "power systems" in nacelles thatafforded significantly better access for maintenance and ventilation of the"twinned" DB 601 component engines in each one, than the Heinkelheavy bomber possessed. Each pair of engines drove a variable-pitch propeller,intended to be a pair of counter-rotating propellers (as the He 177A had usedfor its fourth prototype onwards) with each four-blade propeller driven througha gearbox shared between the "twinned" DB 601 engines forming the"power system", generating 2,700 PS (1,985 kW) each.

The Me 261 had a conventional landing gear with unusually large and bulkylow-pressure tires, much like modern day aircraft tundra tires, which preventedthe aircraft from becoming bogged down on rough grass landing strips. The maingear's design appears to use main struts that rotated through 90° during theirrearwards retraction sequence, with sizable main wheels resting atop theretracted struts (similar to those used on production examples of thecontemporary Junkers Ju 88). Even the Me 261's fully retractable tailwheelpossessed a larger-than-average, low-pressure pneumatic tire.

Construction of three prototypes began at Messerschmitt's Augsburg works duringthe spring of 1939, but progress was slow due to the realisation that war wouldprobably soon break out and the 1940 Summer Olympics would be cancelled. The Me261's original design brief as a long-range reconnaissance aircraft had beenforgotten; now viewed as non-strategic, it was nearly abandoned with all workstopping in August 1939.

The Air Ministry subsequently realised that the Me 261 could still be a usefulvehicle for evaluating long-range operations, and work resumed in the summer of1940.

Me 261 V1
The first flight of the Me 261 V1 was on 23 December 1940, flown by Messerschmitt'stest pilot Karl Baur. Willy Messerschmitt wrote to Ernst Udet in early 1941with the results of the first flight, predicting a range of over 20,000 km(12,000 mi) for the type. The decision to use the DB 606 engine was a problembecause only a few were available for development projects, as most were neededfor types already in production such as the Heinkel He 177. The Me 261 V1 wasbadly damaged during an Allied bombing attack on the Lechfeld Air Base in 1944and eventually scrapped.

Me 261 V2
The first flight of the Me 261 V2 was in early 1941. Official thinking now sawthe Me 261 as a long-range maritime reconnaissance aircraft. Messerschmitt hadrealised that the fuel-carrying nature of the aircraft's wings ruled outfitting armaments to them, and so both prototypes were tested for endurancethrough to 1943. There was a suggestion that one or both be used to droppropaganda leaflets on New York City, but nothing came of the idea before theaircraft were destroyed.[5] The Me 261 V2 was damaged during the same Alliedbombing attack as the V1 and like it was later scrapped.

Me 261 V3
The V3 differed from its predecessors in having two of the June 1940-debuted,DB 610 "power system" engines (which used two DB 605s each, insteadof the paired 601s) and room for two additional crew members. The first flightof the Me 261 V3 was in early 1943; this aircraft had the longest series offlight tests. On 16 April 1943, the Me 261 V3 was flown by Karl Baur over adistance of 4,500 km (2,800 mi) in an elapsed time of 10 hours, setting anunofficial endurance record which could not be confirmed due to war conditions.In July 1943, the Me 261 V3's hydraulics failed on landing and the portundercarriage leg collapsed. The V3 was transported to Oranienburg for repairs,and after that used on a few long-range missions for the Luftwaffe'sreconnaissance division. Its ultimate fate is unknown. (Wikipedia)