Helicopter-Load Tension-Member Study

Abstract

DISCLAIMERSThe findings in this report are not to be construed as an official Uepartment of the Army position unless so designated by other authorized documents.When Government drawings, specifications, or other data are used for any purpose other than in connection with a definitely related Government procurement operation, the U.S. Government thereby incurs no responsibility nor any obligation whatsoever; and the fact that the Government may have formulated, furnished, or in any way supplied the said drawings, specifications, or other data is not to be regarded by implication or otherwise as in any manner licensing the holder or any other person or corporation, or conveying any rights or permission, to manufacture, use, or sell any patented invention that may in any way be related thereto.Trade names cited in this report do not constitute an official endorsement or approval of the use of such commercial hardware or software. DISPOSITION INSTRUCTIONSDestroy this report when no longer needed. Do not return it to the originator. / -madUnclassified Security CUt>ific»tton DOCUMENT CONTROL DATA R&D nmciNATiNC ACTIVITV n ntf.nrmf •uthortThe objectives of this program were to analyze technology applicable to tension members at it relates to the functional requirements of heavy outslzed loads externally suspended from helicopters, and to develop a comprehensive design theory and conceptual designs for tension members which will provide a basis for future detail design, fabrication, and test programs.The tension-member concepts selected for study Included wire rope, wire-rope belt, synthetic rope, synthetic tape, steel tape, roller chain, and jointed links. A weightedparameter technique was used to begin evaluation of these candidate concepts, followed by an analysis of practical considerations with reference specifically to the 1972, 1975, jj and 1980 time frames.The results of this study Indicate that, on a long-term basis, synthetic tape and wirerope belt are the most promising concepts. Only wire rope Is acceptable In the short term (1-2 years). Problems that remain to be solved for synthetic tape Include high aerodynamic drag and high stored elastic energy. Wire-rope belt Is an untried concept for this high-load application. Since high-strength synthetic material Is being studied In other programs, wire-rope belt was chosen for the preliminary design phase of this program.