Akaflieg Darmstadt Munich DM-1

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Akaflieg Darmstadt Munich DM-1
The DM-1
Type: Experimental airplane
Design country:

German Reich NSGerman Reich (Nazi era) German Empire

Manufacturer:

Akaflieg Darmstadt
Akaflieg Munich

First flight:

not flown

Number of pieces:

1

The Akaflieg Darmstadt Munich DM-1 was an experimental aircraft of the student pilot groups Akaflieg Darmstadt and Akaflieg Munich . It served as a non-motorized test vehicle for the supersonic project Lippisch P.13a . The aircraft was to be towed to altitude by mistletoe tow on a Siebel Si 204 and later on a Douglas DC-3 and, in a dive, would reach speeds of up to 560 km / h. However, the plans were abandoned in favor of a test in the wind tunnel .

history

The rear of the DM-1
The DM-1 being transported away by the US Army
The DM-1 after extensive changes by the NACA

During the National Socialist era, the Academic Aviation Groups in Germany received projects and funding from the Reich Aviation Ministry . Akaflieg Darmstadt worked on one of these projects in collaboration with Alexander Lippisch under the designation D-33. But when the students' workshops were bombed in September 1944, they moved to Prien am Chiemsee and developed the project under the name DM-1 together with Akaflieg Munich. The aircraft should be towed to great heights in order to then examine the flight characteristics of the delta wing aircraft in a dive at high speeds. Wind tunnel investigations were still carried out in Vienna, but before the first flight could be carried out, American troops occupied Prien am Chiemsee on May 3, 1945.

From April 1945, individual US Army Air Force (USAAF) teams accompanying the combat troops collected information about secret Air Force projects under the code name LUSTY (LUftwaffe Secret TechnologY). The unfinished DM-1 in Prien, where aerodynamicist Theodore von Kármán from the California Institute of Technology examined the machine and arranged for it to be completed, also belonged to the looted goods . During this time, the commanding general of the 7th US Army, George S. Patton and Charles Lindbergh, also visited the student workshops in Prien. In November 1945, the DM-1 was completed under the direction of Hans Zacher . The first flights were to take place in Germany with a C-47 as a towing machine, but finally the USAAF decided to ship the DM-1 to the USA.

There she arrived in January 1946 and was taken to the large wind tunnel of the Langley Research Center of the NACA , the predecessor of NASA , for wind tunnel investigations . The aircraft was extensively tested on the ground but never flown. In the meantime, Alexander Lippisch was also brought to the USA, where he worked as an advisor to the Air Materiel Command at Wright Field. Although his name is not mentioned in any official NACA document, he probably also acted in an advisory capacity on testing the DM-1 at Langley. Extensively modified several times, the machine was finally handed over to today's Smithsonian National Air and Space Museum in early 1950 .

The DM-1 brought a lot of knowledge that later flowed into Delta aircraft projects such as the Convair XF-92 . The DM-1 can be viewed at the Steven F. Udvar-Hazy Center near Washington, DC (as of 2020).

construction

The construction of the DM-1 has been kept as simple as possible. It consisted mainly of wood, plywood and welded steel pipes. The cockpit is located in the front part of the vertical fin , which runs the entire length of the aircraft. A floor window was installed in the cockpit for better visibility at high angles of attack (approx. 35 ° on landing).

During the wind tunnel investigations by the NACA, the external appearance of the DM-1 was changed significantly. So sharp edges were attached to the fuselage and the fin was greatly reduced. The canopy of a Lockheed P-80 was used for the cockpit . The changes made it possible to increase the lift coefficient from 0.6 to 1.32.

variants

At the same time, the students worked on motorized further developments, from which Alexander Lippisch distanced himself, however, as he was no longer actively involved in these designs. The DM-2 was to be equipped with a Walter rocket engine from the inventor Hellmuth Walter and the lying pilot was to reach a speed of 6000 km / h. The further developments DM-3 and DM-4 should even reach 10,000 km / h. These projects were all discontinued after the end of the war and would have had little chance of achieving the unrealistic performance data.

Technical specifications

Parameter Data
crew 1
length 6.32 m
span 6 m
Wing area 19.9 m²
Wing extension 1.8
Glide ratio 7th
Top speed 560 km / h
Empty mass 375 kg
Max. Takeoff mass 460 kg

See also

literature

  • Hans-Peter Dabrowski: Supersonic fighter Lippisch P.13 and experimental glider DM-1 . Podzun-Pallas Verlag, Stuttgart 1986, ISBN 978-3-7909-0298-3 .
  • Bill Yenne: Convair Deltas - From Seadart to Hustler , Specialty Press, 2009, ISBN 978-1-58007-118-5 , p. 12 f.

Web links

Commons : Akaflieg Darmstadt Munich DM-1  - Collection of images, videos and audio files

Individual evidence

  1. ↑ a b c DM-1 on the Akaflieg Munich website , accessed on July 30, 2012
  2. ↑ Bruno Lange: Type manual of German aviation technology . In: German aviation . tape 9 . Bernard & Graefe Verlag, Koblenz 1986, ISBN 3-7637-5284-6 , p. 207 .
  3. ↑ The DM-1 at the Smithsonian National Air and Space Museum , accessed August 10, 2020
  4. ↑ Hans-Peter Dabrowski: Supersonic fighter Lippisch P.13 and Versuchsgleiter DM-1 , Podzun-Pallas Verlag, Stuttgart 1986, ISBN 978-3-7909-0298-3 , p. 10
  5. ↑ Wind tunnel tests for DM-1: NACA Research Memorandum L7F16, p. 22, Fig. 4 , accessed on July 31, 2012
  6. ↑ Hans-Peter Dabrowski: Supersonic fighter Lippisch P.13 and Versuchsgleiter DM-1 , Podzun-Pallas Verlag, Stuttgart 1986, ISBN 978-3-7909-0298-3 , p. 43