Observations and implications of natural laminar flow on practical airplane surfacesThe results of natural laminar flow (NLF) experiments conducted by NASA to determine if modern aircraft structures can benefit from NLF as do sailplanes are presented. Seven aircraft, ranging from a Cessna 210 to a Learjet 28/29, with relatively stiff skins were flown in production configurations with no modifications. Measurements were made of the boundary-layer laminar to turbulent transition locations on various aerodynamic surfaces, the effect of a total loss of laminar flow, the effect of the propeller slipstream on the wing boundary-layer transition and the boundary-layer profiles, the wing section profile drag, the effect of flight through clouds, and insect debris contamination effects. Favorable pressure gradients for NLF were concluded to be feasible up to a transition Reynolds number of 11 million. Laminar flows were observed in propeller slipstreams, and insects were found to cause transition 1/4 of the time.
Document ID
19820057358
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Holmes, B. J. (NASA Langley Research Center Hampton, VA, United States)
Obara, C. J. (Kentron Technical Center Hampton, VA, United States)
Date Acquired
August 10, 2013
Publication Date
January 1, 1982
Subject Category
Aerodynamics
Meeting Information
Meeting: International Council of the Aeronautical Sciences