40,000-POUND-CAPACITY HEAVY-LIFT HELICOPTER EXTERNAL CARGO HANDLING SYSTEM DESIGN STUDY
AAI CORP COCKEYSVILLE MD
Pagination or Media Count:
The purpose of this program was to design a helicopter hoist system capable of lifting 40,000 pounds. Desired features of the hoist system included a weight limitation of 4,000 pounds and the ability to provide either a 1- and 2-point load suspension system or a 1- and 4-point load suspension system. Major areas of investigation included a study of primary tension members the relative advantages of multi-drum and single-drum hoist systems single wrap and overlaying of cables on hoist drums and the desirability of including vibration isolation components between the external load and the helicopter. Through study and tests, it was determined that it was possible to provide a combined system which permits 1-, 2-, and 4-point load suspension. This feature is achieved by use of a single cable drum winding four separate cables. Varying the method of reeving the cables permits the selection of either a 1-, 2-, or 4- point load suspension system. Load attitude and cable loading may be adjusted by means of four hydraulic control cylinders included in the system. Using a single drum with four cables eliminates the complex synchronization problems associated with a multi-drum drive system.