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Ljungstrom Internal Propulsion Aeroplane Projects - "Jet" Aircraft from 1928! - Luftwaffe and Allied Air Forces Discussion Forum

Olof Ljungstrom, an engineer in the aircraft division of the Ford Motor Company, developed a propulsion system featuring boundary layer removal by means of a piston engine driving an axial flow turbine blower inside the aircraft. In 1928, he proposed a giant seaplane and the small monoplane pictured above, both of which were powered with this system. The accompanying image gallery reproduces the proposal documents, correspondence with NACA, and several photos and drawings of these futuristic though flawed machines.

Ljungstrom Internal Propulsion Aircraft Projects (1928)
https://retromechanix.com/ljungstrom-internal-propulsion-aircraft-projects-1928/nggallery/image/image-1704

In 1928, Olof Ljungstrom of Detroit, Michigan submitted a pair of unusual aircraft proposals to NACA which featured boundary layer removal via a primitive form of jet engine, in which a piston engine drove an axial flow turbine blower inside the aircraft. The power plant is reminiscent of that used by the Caproni Campini N.1, which first flew August 27, 1940. However, the Ljungstrom design did not feature a combustion chamber and was less advanced than the N.1, which was not a true jet itself but a “motorjet” or ducted fan type. Ljungstrom appears to have been employed as an engineer in the aircraft division of the Ford Motor Company, as W.B. Mayo, the head of this organization, sent the proposals to Edward P. Warner, Assistant Secretary of the Navy for Aeronautics, on Ljungstrom’s behalf.