NTRS - NASA Technical Reports Server

Back to Results
Energy-absorbing-beam design for composite aircraft subfloorsData have been presented from the design support testing of composite energy absorbing (EA) aircraft subfloor structures. The focus of the current study is the design and testing of subfloor structural concepts that would limit the loads transmitted to occupants to less than 20 g at crush speeds of approximately 30 fps. The EA composite subfloor is being designed to replace an existing noncrashworthy metallic subfloor in a composite aircraft prior to a full-scale crash test. A sandwich spar construction of a sine wave beam was chosen for evaluation and was found to have excellent energy absorbing characteristics. The design objective of obtaining sustained crushing loads of the spar between 200-300 lbf/inch were achieved for potentially limiting occupants loads to around 20 g's. Stroke efficiency of up to 79 percent of the initial spar height under desired sustained crushing loads was obtained which is far greater than the level provided by metal structure. Additionally, a substantial residual spar stiffness was retained after impact, and the flange integrity, which is critical for seat retention, was maintained after crushing of the spars.
Document ID
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Carden, Huey D.
(NASA Langley Research Center Hampton, VA, United States)
Kellas, Sotiris
(Lockheed Engineering and Sciences Co. Hampton, VA, United States)
Date Acquired
August 16, 2013
Publication Date
January 1, 1993
Publication Information
Publication: In: AIAA(ASME)ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, 34th and AIAA/ASME Adaptive Structures Forum, La Jolla, CA, Apr. 19-22, 1993, Technical Papers. Pt. 1 (A93-33876 1
Publisher: American Institute of Aeronautics and Astronautics
Subject Category
Aircraft Design, Testing And Performance
Report/Patent Number
AIAA PAPER 93-1339
Accession Number
Distribution Limits

Available Downloads

There are no available downloads for this record.
No Preview Available