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This study continues previous experimental studies which review the characteristics of the side impact exposure to the human head. We conducted a series of two experiments. The first series included four sequential impacts which were performed on a single embalmed specimen. This series of impacts showed a good correspondence between peak head acceleration and HIC and confirmed the adequacy of instrument placement and data analysis. The second series studied five impacts performed on individual unembalmed cadavers. The results suggest that side impacts produced pressure gradients in the brain. These superimposed gradients were proportional to the magnitudes of the head acceleration components. The largest component was found to be in the direction of impact and produced positive pressures near the impact and negative pressures opposite the impact. We found that a pressure limiting mechanism acted on the contra-coup side of the brain.

This paper describes the latest ideas on a modified process and methods for the clearance of aircraft to the lightning external environment. It covers the whole sequence from the specification of equipment qualification requirements to the demonstration that these are within the electromagnetic environment in which the equipment is installed in the event of strikes up to the severity of the internationally agreed full-threat level. In particular, the process includes computational modelling and whole aircraft/system testing as standard tools, requiring additional levels of confidence where either one is not available or un-feasible. It also contains methods proposed to improve the integrity of whole aircraft testing; an essential concomitant of the availability of computational techniques and the need to validate them. The reasons for changes to currently accepted practice will be explained and justified.