The capsule returned once again under parachutes but, this time, did a test descent with only two parachutes before finishing with a brief pulse of retro rocket propulsion to slow the ground impact velocity to 4.8 km/h (3 mph). The two parachutes "slowed the descent to 23 mph, as opposed to the usual 16 mph with three parachutes". Crushable bumpers are used to further reduce the landing shock through energy-absorbing deformation.[59]