The military version of blackboxes called Automatic Deployable Flight Recorders (ADFR) do the same job as those used in civil aircraft with one major difference: on impact the ADFR separates from the aircraft. Mounted flush into the skin of the aircraft’s tail, the ADFR is an airfoil. Upon release, it enters the aircraft’s slipstream, flying it away from the crash. It its buoyant, so should it land in water, it will float.
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