RDG006016 Technical progress continues to create a demand for information which will enable men to operate effectively in a new weapons systems; progress in engineering and electronics requires a collateral research effort in human adaptation. A large proportion of NMRIs studies are directed to meet this need. In the Vibration Laboratory, shown in this photograph, measurements of human tolerance to low frequency vibration are made during research on the protection of personnel against vibration-induced injuries in helicopters, low-level attack aircraft, and hydrofoil ships. High speed x-ray motion pictures are taken to record the motion of the subjects internal organs during the vibration tests.