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The role of apparent mass effects in determining the magnitude of parachute opening shock force have been studied for many years. The ideas proposed in this report present arguments that the apparent mass effects may be neglected in calculating parachute opening shock force when using the dynamic drag area method of solution. It is also argued that the partial collapse of round personnel parachutes, at full inflation, may be due to the inertia of the entrapped air mass in concert with an air mass from aft of the canopy. Approved by