Design and crash test of composite helicopter frame structure

4 Design and crash test of composite helicopter frame structure 

The upper frame structure was composed of back-to-back flanged C-sections bonded together. The composite materials used were Hexply M18/l/43%/G939-220gsm 4HS fabric, laminate thickness in the webs and flanges varied between 

Flgnre 10.13 As manufactured frame stmcture with detaiis of energy absorption subfloor. 

Impact plate 1 Impact plate 2 I Base plate 

The HS video films of the tests show the sequential failure modes observed and give an insight into the effectiveness of the design concept and triggering of the EA subfloor. Sequences fix m the videos and details of the strain gauge data are given in [31]. 

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