Background
TWA Flight 5787 departed New York-JFK to conduct training and proficiency check maneuvers at the National Aviation Facilities Experimental Center (NAFEC) at Atlantic City Airport. The aircraft was crewed by a first captain in the left seat, an instructor pilot in the right seat, a flight engineer at his station, and two other captains observing on the flight deck.
Flight Sequence
After landing on runway 13, the flight requested and received clearance to taxi to the end of the runway, execute a 180-degree turn, and take off on runway 31. Before takeoff, the instructor pilot briefed the captain to anticipate a simulated engine failure after V1, perform a three-engine climbout, and then request vectors for a precision ILS approach to runway 13 using the flight director system.
Takeoff commenced at 12:20. After reaching V1, the instructor pilot retarded the No. 4 engine to training idle thrust. The takeoff continued, and emergency procedures were executed according to the TWA engine failure emergency checklist. The aircraft was leveled off at 1,500 feet and vectored to intercept the ILS course near the outer marker. The No. 4 engine remained at idle thrust. The instructor pilot directed the captain to execute a simulated three-engine ILS approach and to expect a missed approach at the decision height.
During the approach, the landing gear was extended. After passing the outer marker, flaps were set to full down (50 degrees). The tower cleared TWA 5787 to land.
Hydraulic System Failure
At the decision height, the captain announced a missed approach. He advanced power on engines 1, 2, and 3 and called for "25 Flaps," "Takeoff Power," and "Up Gear." However, neither the flaps nor the landing gear responded; they remained in their previous positions. The aircraft accelerated to 130 knots, and a missed-approach climb was initiated.
Approximately 16 to 18 seconds after the missed approach began, one of the observer pilots commented, "Oh! Oh! Your hydraulic system's zeroed." At an altitude of 300 feet above ground level and an airspeed of 127 knots, all hydraulic pumps were shut down. However, power on the No. 4 engine was not restored.
Accident
Directional control was lost, and the aircraft struck the ground in a right-wing-low, nose-down attitude. The Boeing 707 broke apart and caught fire.