Download or read book Aerodynamic Characteristics of Several Current Helicopter Tail Boom Cross Sections Including the Effect of Spoilers written by John C. Wilson and published by . This book was released on 1986 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerodynamic characteristics were determined of three cylindrical shapes representative of tail boom cross sections of the AH-64, UH-60, and UH-1H helicopters. Forces and pressures were measured in a wind-tunnel investigation. Data was obtained for a flow incidence range from -45 to 90 deg and a dynamic pressure range from 1.5 to 50 psf. These ranges provided data representative of full-scale Reynolds numbers and the full range of flow incidence to which these helicopter tail boom shapes would be subjected at low flight speeds. The effects of protuberances such as tail rotor drive-shaft covers and spoilers were evaluated. The data indicate that significant side loads on tail booms of helicopters can be generated and that the addition of spoilers can beneficially alter the side loads. Although an increase in vertical drag occurs, the net effect through reduction of tail rotor thrust required can be an improvement in helicopter performance. Keywords: Rotorcraft; Aerodynamics; Stability and control; Helicopters; Tail booms.
Download or read book Aerodynamic Characteristics of Several Current Helicopter Tail Boom Cross Sections Including the Effect of Spoilers written by John C. Wilson and published by . This book was released on 1986 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerodynamic characteristics were determined of three cylindrical shapes representative of tail boom cross sections of the AH-64, UH-60, and UH-1H helicopters. Forces and pressures were measured in a wind-tunnel investigation. Data was obtained for a flow incidence range from -45 to 90 deg and a dynamic pressure range from 1.5 to 50 psf. These ranges provided data representative of full-scale Reynolds numbers and the full range of flow incidence to which these helicopter tail boom shapes would be subjected at low flight speeds. The effects of protuberances such as tail rotor drive-shaft covers and spoilers were evaluated. The data indicate that significant side loads on tail booms of helicopters can be generated and that the addition of spoilers can beneficially alter the side loads. Although an increase in vertical drag occurs, the net effect through reduction of tail rotor thrust required can be an improvement in helicopter performance. Keywords: Rotorcraft; Aerodynamics; Stability and control; Helicopters; Tail booms.
Download or read book Two dimensional Aerodynamic Characteristics of Several Polygon shaped Cross sectional Models Applicable to Helicopter Fuselages written by Henry L. Kelley and published by . This book was released on 1992 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Scientific and Technical Publications written by and published by . This book was released on 1987 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Technical Paper written by and published by . This book was released on 1986 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Principles of Helicopter Aerodynamics with CD Extra written by Gordon J. Leishman and published by Cambridge University Press. This book was released on 2006-04-24 with total page 860 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by an internationally recognized teacher and researcher, this book provides a thorough, modern treatment of the aerodynamic principles of helicopters and other rotating-wing vertical lift aircraft such as tilt rotors and autogiros. The text begins with a unique technical history of helicopter flight, and then covers basic methods of rotor aerodynamic analysis, and related issues associated with the performance of the helicopter and its aerodynamic design. It goes on to cover more advanced topics in helicopter aerodynamics, including airfoil flows, unsteady aerodynamics, dynamic stall, and rotor wakes, and rotor-airframe aerodynamic interactions, with final chapters on autogiros and advanced methods of helicopter aerodynamic analysis. Extensively illustrated throughout, each chapter includes a set of homework problems. Advanced undergraduate and graduate students, practising engineers, and researchers will welcome this thoroughly revised and updated text on rotating-wing aerodynamics.
Download or read book NASA Technical Memorandum written by and published by . This book was released on 1990 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1986 with total page 1162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Exploratory Investigation of Aerodynamic Characteristics of Helicopter Tail Boom Cross Section Models with Passive Venting written by Daniel W. Banks and published by . This book was released on 2000 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two large-scale, two-dimensional helicopter tail boom models were used to determine the effects of passive venting on boom down loads and side forces in hovering crosswind conditions. The models were oval shaped and trapeziodal shaped. Completely porous and solid configurations, partial venting in various symmetric and asymmetric configurations, and strakes were tested. Calculations were made to evaluate the trends of venting and strakes on power required when applied to a UH-60 class helicopter. Compared with the UH-60 baseline, passive venting reduced side force but increased down load at flow conditions representing right sideward flight. Selective asymmetric venting resulted in side force benefits close to the fully porous case. Calculated trends on the effects of venting on power required indicated that the high asymmetric oval configuration was the most effective venting configuration for side force retention, and the high asymmetric with a single strake was the most effective for overall power reduction. Also, curves of side force versus flow angle were noticeably smoother for the vented configurations compared with the solid baseline configuration; this indicated a potential for smoother flight in low-speed crosswind conditions.
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1996 with total page 938 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aerodynamic Effect of Strakes on Two dimensional Tail Boom Models of OH 58A and OH 58D Helicopters written by Cynthia A. Crowell and published by . This book was released on 1990 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aerodynamic Effect of Strakes on Two dimensional Tail Boom Models of the OH 58A and the OH 58D Helicopters written by Cynthia A. Crowell and published by . This book was released on 1990 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development in Helicopter Tail Boom Strake Applications in the US written by John C. Wilson and published by . This book was released on 1988 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeronautical Engineering written by and published by . This book was released on 1989 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).
Download or read book Journal of the American Helicopter Society written by American Helicopter Society and published by . This book was released on 1992 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1986-06 with total page 1174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA SP written by and published by . This book was released on 1962 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt:
