German researcher Otto Lutz introduced the swing-piston concept about 1923. Intended primarily as a high pressure compressor or gas generator for relatively high power gas turbine engines for long-range transport aircraft, principal advantages were improved fuel economy, use of Diesel fuel, and a compact design.
To reduce the space occupied by conventional reciprocating engines, cylinders were located inside a liquid-cooled annulus, and were the spaces between members of two sets of piston. Pistons were free floating and, instead of driving connect rods and a crankshaft as in conventional engines, generated compressed and heated gases by recoiling between cushions of charged air, with combustion at the time of maximum compression of each charge. Combustion products either passed directly through a discharge nozzle, furnishing jet propulsion, or through a turbine, to generate power for a propeller or ducted fan.
Two experimental units were briefly tested, but no substantiating data generated. An Allied bombing raid on the plant ended development.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Circa World War II
Germany
PROPULSION-Reciprocating & Rotary
Bussing-NAG Entwicklungsgesellshaft G.m.b. H.
Dr. Otto Lutz
Type: Reciprocating, 6 cylinders, liquid cooled
Power rating: 298 kW (400 hp) at 800 rpm
Displacement: Not available
Bore and Stroke: Not available
Weight: Not available)
Length 97.8 cm (38.5 in.), Width 94.6 cm (37.25 in.), Height 143.5 cm (56.5 in.)
Steel
Wood
Paint
Plastic
Adhesive
Cork
Fabric
Paper
String
Cadmium Plating
Copper Alloy Plating
A19670099000
Transferred From USAAF Technical Museum, WPAFB
National Air and Space Museum
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