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Aircraft seating systems are evaluated utilizing a variety of impact conditions and select injury measures. Injury measures like the Head Injury Criterion (HIC) are evaluated under standardized conditions using anthropomorphic test devices such as those outlined in 14 CFR part 25. An example test involves decelerating one or more rows of seats and allowing a lap-belted ATD to engage components in front of it, which typically include the seatback and its integrated features. Examples of head contact surfaces include video monitors, various plastic and composite fascia, and a wide range of seat back materials. The HIC, and other injury measures such as Nij, can be calculated during such impacts. It has been shown in other safety applications that the friction between a headform and contact surface can affect the test results.

Aircraft seating systems are evaluated utilizing a variety of impact conditions and selected injury measures. Injury measures like the Head Injury Criterion (HIC) are evaluated under standardized conditions using anthropomorphic dummies such as those outlined in 14 CFR part 25. An example test involves decelerating one or more rows of seats and allowing a lap-belted dummy to impact components in front of it, which typically include the seatback and its integrated features. Examples of head contact surfaces include video monitors, a wide range of seat back materials, and airbags. The HIC, and other injury measures such as Nij, can be calculated during such impacts. A minimum test pulse, with minimum allowable acceleration vs time boundaries, is defined as part of the regulations for a frontal impact. In this study the effects of variations in decelerations that meet the requirements are considered.

Frame rail design advances for the heavy truck industry provide numerous opportunities for enhanced protection of fuel storage systems. One aspect of the advanced frame technology now available is the ability to vary the frame rail separation along the length of the truck, as well as the depth of the frame. In this study, the effect of incorporating the fuel storage system within advanced technology tapered frame rails was evaluated using virtual testing under impact conditions. The impact performance was evaluated under a range of horizontal impacts conditions. The performance observed was quantified and then compared with previous testing of baseline diesel tank systems. Fuel storage system impact performance metrics over the range of crash conditions considered were quantified using virtual testing methods. The results obtained from the application of the impact performance evaluation methodology were then described.

The incidence of fire in heavy trucks has been shown to be about ten times higher under crash conditions than occurs in passenger vehicles. Fuel tank protection testing defined in SAE standard J703 was originally issued in 1954 and presently echoes federal regulations codified in 49 CFR 393. These tests do not reflect dynamic impact conditions representative of those that can be expected by heavy trucks on the road today. Advanced virtual testing of current and alternative fuel tank designs and locations under example impact conditions is reported. Virtual testing methods can model vehicle to vehicle and vehicle to fixed object impacts. These results can then be utilized to evaluate and refine fuel tank protection system design approaches.

Rollover test equipment is of interest in the development of rollover protection system designs. The Controlled Rollover Impact System (CRIS) by Exponent and the Jordan Rollover System (JRS) from the original founder of VIA Systems represent two such systems available. The two systems represent significantly different approaches to the same problem; the CRIS utilizes a structure moving over the ground, while the JRS utilizes a rotating vehicle over a moving ground. Finite Element (FE) modeling of CRIS impacts has been presented previously. In this paper, the ability to model the JRS system is demonstrated. A Finite Element model of the JRS was created and compared with an over-the-ground rollover under the same conditions. An analysis using Finite Element models of a production and roll-caged vehicles and Hybrid III dummies with the CRIS and JRS devices under the same impact conditions then was conducted. The results of the analysis are provided and discussed.

The Federal Motor Vehicle Safety Standard 226 (FMVSS 226) ejection mitigation standard proposes to measure the performance of ejection mitigation countermeasures (like side curtain airbags) in side impacts and rollovers. An ejection impactor, consisting of a head form attached to a shaft, is propelled at the airbag system at different locations, and the ability of the system to prevent complete or partial ejection out of the side window portals is documented. The friction between the head form and airbag can affect the performance of the airbag to retain the impactor, particularly when the impactor strikes at the bottom of the airbag near the windowsill level. In this study, friction tests were conducted to measure the friction coefficients between a head form scalp material and airbag fabric, human hair and airbag fabric, and human skin and airbag fabric.