A marine propulsion drive unit is provided with two energy absorbing structures, one comprising a crushable or deformable nose cone or leading edge of a driveshaft housing and the other comprising a frangible interface that allows the drive unit to separate from the hull of a marine vessel. The crushable or deformable nose cone is configured to absorb energy at relatively low impact velocities with submerged structures and the frangible interface is configured to absorb energy and then detach from the hull of the marine vessel at higher impact velocities.