sentences:  Reports also note an apparent fracture of the booster's forward segment casing and a fractured bracket that held an actuator, part of the SRM's nozzle vectoring system.A NASA memo states that engineers believe that the lower segment buckled when the first stage landed at a much higher speed than designed as a result of one of three main parachutes failing to deploy, as well as the failure of a second main parachute to remain deployed.It is unclear, at this point, what caused the apparent casing fracture and broken bracket, and NASA has not commented on this damage.