Event Description
During preparation for a flight in a Boeing 757, the first officer (FO) inadvertently computed the takeoff data using data intended for a Boeing 767 aircraft. The resulting V1, VR, and V2 speeds were calculated as 115 knots, 118 knots, and 129 knots, respectively. The correct speeds for the Boeing 757 should have been 145 knots, 148 knots, and 152 knots. The captain did not confirm the V-speed computation, and both pilots set their airspeed bugs at the improper speeds.
During lift-off, the aircraft was overrotated, causing the lower aft fuselage to contact the runway. The crew noted a 'jolt' but elected to continue to their destination after discussing the situation with maintenance personnel.
Damage
After landing, damage was noted to the lower aft skin, aft pressure bulkhead, and associated structure.