Download or read book Analysis of a System to Prevent Helicopter Rotor blade Airframe Strikes written by United States. Army Research Office and published by . This book was released on 1989 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of a System to Prevent Helicopter Rotor Blade airframe Strikes written by Barnes Warnock McCormick (Jr.) and published by . This book was released on 1989 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of a System to Prevent Helicopter Rotor Blade Airframe Strikes written by United States. Army Research Office and published by . This book was released on 1989 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rotor blade-airframe strikes are rare but they do occur. Three areas of the airframe are particularly vulnerable: the tail boom, canopy and, in the case of the underslung, teetoring rotor, the rotor shaft. This latter case is known as mast bumping. This report studies a system to prevent a helicopter rotor blade from striking any part of the airframe. Essentially, the system continuously predicts ahead the rotor blade flapping in response to an input such as pilot control or an atmospheric disturbance. If a blade strike is predicted to occur then an appropriate feedback control is applied to alter the future flapping. The prediction is then begun again with the altered control. In the actual system, an enunciator might warn the pilot at the time that he is attempting a control input which could be hazardous. Two somewhat independent approaches to the design of the controller are taken. One of the programs is entirely numerical in its approach. The other uses modern control theory and considers the preliminary aspects of implementing the controller in digital hardware. Both methods indicate the feasibility of preventing excessive flapping, although the question of implementation in a dedicated microprocessor is not fully resolved. Helicopter rotor control systems.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Research in Progress written by and published by . This book was released on 1988 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technical Reports Awareness Circular TRAC written by and published by . This book was released on 1989-08 with total page 568 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 1989-11 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Lawyers Desk Reference written by and published by . This book was released on 1993 with total page 1388 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 1990 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of the Dynamic Properties of Helicopter Rotor Blades and of the Complete Rotor airframe Structure written by and published by . This book was released on 1973 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1982 with total page 1094 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1982 with total page 1094 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Public Administration Series Bibliography written by and published by . This book was released on 1990 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Helicopter obstacle strike tolerance concepts analysis written by Bharat P. Gupta and published by . This book was released on 1979 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of Stall Flutter of a Helicopter Rotor Blade written by Peter Crimi and published by . This book was released on 1973 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study of rotor blade aeroelastic stability was carried out, using an analytic model of a two-dimensional airfoil undergoing dynamic stall and an elastomechanical representation including flapping, flapwise bending and torsional degrees of freedom. Results for a hovering rotor demonstrated that the models used are capable of reproducing both classical and stall flutter. The minimum rotor speed for the occurrence of stall flutter in hover, was found to be determined from coupling between torsion and flapping. Instabilities analogous to both classical and stall flutter were found to occur in forward flight. However, the large stall-related torsional oscillations which commonly limit aircraft forward speed appear to be the response to rapid changes in aerodynamic moment which accompany stall and unstall, rather than the result of an aeroelastic instability. The severity of stall-related instabilities and response was found to depend to some extent on linear stability. Increasing linear stability lessens the susceptibility to stall flutter and reduced the magnitude of the torsional response to stall and unstall.

Download or read book Aeronautical Engineering written by and published by . This book was released on 1971 with total page 580 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 In flight Escape Systems for Helicopters Should be Developed to Prevent Fatalities written by United States. General Accounting Office and published by . This book was released on 1973 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: