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It is shown that the maximum acceleration that a person may encounter at a given time after separation of his escape unit from a damaged, unrecoverable aircraft is dependent only on the velocity of the aircraft. Acceleration histories determined from flight tests indicate that these theoretical maximums are reasonable and practical at least in the subsonic case. Lt. Colonel J. P. Stapp of the Aero Medical Laboratory has reported (see paragraph 3) that high rate of acceleration onset during a fixed time produces injuries not found at lower onset rates. On the hypothesis that decay rates may be of comparable interest it is shown in this report that decay acceleration rates are functions of the initial acceleration and speed of the escape unit. The accelerations parallel to and normal to the spine of a person in a tumbling escape unit are calculated for an assumed hypothetical case. The effects of these alternately increasing and decreasing accelerations on the person may be described as a shaking phenomena which may be beneficial to the escaping person.

Improved numerical results are obtained for the spectrum of turbulence based on Heisenberg's elementary theory during the stage of decay in a nonstationary process, which is discussed in Chandrasekhar's 1949 paper. The choice of the form of the differential equation is examined from the viewpoint of its sensitivity in numerical computations to variations of the basic parameter.