Search Results

The dynamic impact test of a section of passenger airplane fuselage provided an opportunity to measure the loads transferred to an airplane floor by the passenger seat legs. Since placement of a force transducer between the seat legs and the aircraft floor could not be done without adversely affecting the validity of the measurements, it was necessary to develop an alternative instrumentation technique. The method chosen was to install strain gages on the legs of the seats and to calibrate the strain gage output in terms of forces transmitted to the floor of a rigid test fixture during sled tests of each seat. The instrumentation methods, the acquired data, and an analysis of the results of the calibration procedure are presented in this paper.

The use of injury criteria as a basis for the acceptance of seats and restraint systems designed to possess some capacity for crash injury protection has been common for several years in military aircraft and automotive systems, but has only recently been considered for civil aircraft systems. This paper will present the background for the concept of “injury criteria” as distinct from “voluntary human tolerance,” and will explain methods used in developing certain criteria which are most likely to be useful in evaluating civil aircraft seat and restraint system performance. Finally, techniques for using the measurements in testing will be summarized, and guidance will be provided to the system designer which may assist in meeting the goals established by the criteria.

The General Aviation Safety Panel has developed recommendations for the performance of seating and restraint systems for small aircraft with fewer than 10 passenger seats, and has presented those recommendations to the Federal Aviation Administration as part of the “Small Airplane Airworthiness Review Program”. This paper presents the results of dynamic sled tests conducted at the Civil Aeromedical Institute in support of the Panel's work, and discusses the background for injury criteria and other specific parts of the recommendations.

Increased concern regarding occupant protection for aircraft crashes has expanded efforts toward development of crashworthy aircraft systems. The purpose of a crashworthy seat, restraint, or interior design is to reduce the probability and severity of injury to the occupant during a crash. In order to evaluate the performance of those systems before they are placed into production, the designer should consider the value of proper dynamic testing. The results of dynamic test should indicate the likelihood of injury to the aircraft occupant. However, test results can be greatly influenced by test techniques. This paper presents current approaches to evaluating dynamic test results in terms of likelihood of injury to the human occupant, discusses the limitations and background of those approaches, and presents technical considerations for selection and use of anthropomorphic dummies, test conduct, etc.