A discussion of the modes of failure of bumper-hull structures with application to the meteoroid hazard

The impact of double-sheet structures is discussed, and typical impact-performance curves, determined by the physical processes by which the rear sheet fails, are defined.It is concluded that, in order for a bumper-hull system to perform effectively, the front-and rear-sheet thicknesses must be larger than certain minimum limits.Tentative values for these limits are: the front sheet should be thicker than 0.25 times the diameter of the largest probable meteoroid; the rear sheet should be thicker than 0.50 times the diameter of the largest probable meteoroid; and the rear sheet should be thicker than the front sheet.Also, it is concluded that if the sheet-thickness ratios are selected according to both high-and low-speed results (observing the above thickness-ratio minimums), and the sheet spacing is selected according to low-speed results, the structure will pcrform satisfactorily for all probable impact conditions.17.Key Words (Suggested by Authorb)) Hypervelocity impact Meteoroid hazard Meteor bumper Impact phenomena 18. Distribution Statement Unclassified -Unlimited 19.Security Classif.(of this report) 22. Price' 21.NO. of Pages 20.Security Classif.(of this page)