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Model Investigation of the Landing Characteristics of a Reentry Spacecraft with a Vertical-cylinder Air Bag for Load Alleviation

出版	National Aeronautics and Space Administration, 1962
URL	http://books.google.com.hk/books?id=PTeUMQEACAAJ&hl=&source=gbs_api

註釋Analytical and experimental investigations were made to determine the landing characteristics of a re-entry spacecraft equipped with a verticalcylinder air bag for impact load alleviation. Assuming a rigid body and isothermal air compression and expansion, computations were made to determine accelerations for a landing on concrete from a flight-path angle of 90 degrees (vertical flight path) at a contact attitude of 0 degrees. Two models (1/6 and 1/2 scale) of the air-bag system were tested. A 1/6-scale dynamic model of a spacecraft--air-bag configuration proposed for manned re-entry was landed on concrete, on sand, and in calm water from various flight paths for a range of contact attitudes. Reasonable agreement between computed and experimental data indicates that the scaling technique developed is satisfactory for prediction of fullscale characteristics from model tests with air bags in atmospheric environment. The maximum accelerations obtained during landings on sand were about 11g along the X-axis and about 8g along the Z-axis. The maximum accelerations obtained during landings in water were about 10g along the X-axis and about 6g along the Z-axis. (Author).