Akaflieg Darmstadt/Akaflieg München DM1
The Akaflieg Darmstadt Munich DM -1 was an experimental aircraft the student Fliegergruppen Akaflieg Darmstadt and Munich Akaflieg. She served as a non-motorized test vehicle for the supersonic project Lippisch P.13a. The aircraft was towed by mistletoe on a Siebel Si 204 and later on a Douglas DC-3 to be towed on the amount and swooping reach speeds of up to 560 km / h. However, the plans in favor of testing in the wind tunnel were abandoned.
History
In the era of National Socialism, the Academic Flying Group in Germany were assigned projects and financial resources from the Ministry of Aviation. On one of these projects Akaflieg Darmstadt worked in collaboration with Alexander Lippisch under the name D- 33rd But when the workshops the students were bombed in September 1944, they moved to Prien am Chiemsee and developed the project under the name DM- 1 together with the Akaflieg Munich. The aircraft should be towed to great heights to investigate then swoop the flight characteristics of Deltaflüglers at high speeds. In Vienna, wind tunnel studies have been performed, but before the first flight could be carried out, in 1945, American troops occupied Prien am Chiemsee on May 3.
As of April 1945, collected individual teams of the U.S. Army Air Force ( USAAF), which accompanied the combat troops, under the code name LUSTY ( Luftwaffe Secret Technology) information about secret projects of the Air Force. To plunder included the unfinished DM- 1 in Prien where the aerodynamicist Theodore von Kármán examined from the California Institute of Technology, the machine and its completion prompted. During this time, the commanding general of the U.S. 7th Army George S. Patton and Charles Lindbergh visited the workshops of students in Prien am Chiemsee. In November 1945, the DM -1 was completed and the first flights should be carried out with a C -47 as a tow plane, but eventually the USAAF decided the DM- 1 in the USA to ship.
There she met a in January 1946 and was brought to the wind tunnel studies on large wind tunnel at the Langley Research Center of the NACA, the predecessor of NASA. The aircraft was extensively tested on the ground, but never flown. In the meantime, Alexander Lippisch was taken to the USA where he on the Wright Field was a consultant of the Air Materiel Command. Although his name is mentioned in any official NACA document, it probably has been involved in an advisory capacity even with the tests of the DM- 1 in Langley. Modified multiple extensive, the machine was finally today Smithsonian National Air and Space Museum handed over in early 1950.
The DM -1 brought many insights, eventually resulting in Delta aircraft projects such as the Convair XF -92. The DM -1 can now (as of 2012) in the Steven F. Udvar- Hazy Center near Washington DC be visited.
Construction
The construction of the DM- 1 was kept as simple as possible. It consisted above all in wood, plywood and welded steel tubes. The cockpit is located in the front part of the fin that runs the entire length of the aircraft. For better visibility at high angles of attack (about 35 ° when landing ) a floor window was installed in the cockpit.
During the wind tunnel tests by the NACA, the external appearance of the DM- 1 was greatly changed. So sharp edges were attached to the hull and greatly reduced the fin. For the cockpit the hood of a Lockheed P-80 was used. Due to the changes in the lift coefficient was increased from 0.6 to 1.32.
Variants
The students worked simultaneously on motorized developments, of which Alexander Lippisch, however distant, because he no longer actively involved in these designs. Thus, the DM-2 should be equipped with a Walter rocket engine of the inventor Hellmuth Walter and reach the pilot lying a speed of 6000 km / h. Further developments DM -3 and DM -4 should do 10,000 km / h reached. These projects were all no longer continued after the war and would have had little chance to reach the unrealistic performance.