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Nasa research on the aerodynamics of jet vtol engine installationsThis paper summarizes some of the more pertinent results of NASA investigations related to the aerodynamics of jet VTOL engine installations. It shows that there is a base loss in hovering due to suction forces creased on the underside of the fuselage by the entrainment of ambient air in the slipstream, and that the magnitude of this effect is related to the turbulence in the jet stream and its consequent rate of mixing with ambient air. It also shows that there are large lift losses and pitching moments due to jet-free-stream interference and that these characteristics can be significantly altered by proximity to the ground. And, finally, it shows that simple bellmouth inlets give good pressure recovery and low distortion for vertically mounted lift engines if the inlet lip radius is sufficiently large, but that such inlets are not suitable for windmill starting of the engines.
Document ID
19650025397
Acquisition Source
Langley Research Center
Document Type
Technical Memorandum (TM)
Authors
Richard E. Kuhn
(Langley Research Center Hampton, United States)
Marion 0. McKinney, Jr.
(Langley Research Center Hampton, United States)
Date Acquired
September 2, 2013
Publication Date
October 25, 1965
Subject Category
Propulsion Systems
Report/Patent Number
NASA-TM-X-56820
L-4506
Report Number: NASA-TM-X-56820
Meeting Information
Meeting: AGARD Specialist Meeting on Aerodynamics of Power Plant Installation
Location: Tullahoma, TN
Country: US
Start Date: October 25, 1965
End Date: October 27, 1965
Sponsors: North Atlantic Treaty Organization
Accession Number
65N34998
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Keywords
VTOL AIRCRAFT
JET ENGINE
NASA PROGRAM
INSTALLATION
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