Douglas DC-8-63F accident at Jamaica, New York, 20 Sept 1975 (N6161A)

Accident narrative

About 0355 e.d.t. on September 20, 1975, Airlift International Flight 101, a McDonnell-Douglas DC-8-63F (N6161A), struck navigational aid structures beyond the departure end of runway 22L while taking off from John F. Kennedy International Airport in Jamaica, New York. The accident occurred in darkness and reduced visibility. The four occupants were uninjured, but the aircraft sustained slight damage and several ground components were destroyed.

### The flight

Flight 101 was a scheduled cargo flight from New York to San Francisco International Airport. Three crewmembers and a nonrevenue rider were aboard.

Before departure, the captain checked the flight plan and weather, and accepted the weight and balance calculations computed by the station agent for a takeoff on runway 22R. The aircraft's gross weight was computed to be 347,819 pounds. Runway 22R is 11,352 feet long.

The flight left the gate at 0345. The ground controller cleared the flight to taxi, reporting the weather as an indefinite ceiling of zero, sky obscured, and visibility of 1/8 mile in fog. Because the visibility on runway 22R was below takeoff minimums, the captain accepted a clearance for runway 22L, which is 8,400 feet long and had an adequate runway visual range.

While the captain was occupied with taxiing in the low-visibility conditions, he asked the first officer to check if runway 22L was adequate for takeoff. The first officer looked at a taxiway and parking facilities chart, which did not contain runway limitations data, and advised that the runway was acceptable. The crewmembers did not refer to the Runway Analysis Manual carried in the aircraft.

During the taxi, the pilot of another aircraft on the same ground control frequency reported that his aircraft was too heavy to take off from runway 22L. The ground controller suggested runway 13R, which was 14,572 feet long and also available to Flight 101, and the other pilot accepted.

Flight 101 changed to tower control and was cleared for takeoff on runway 22L. The first officer made the takeoff from a standing start, using the speeds that had been computed for the longer runway 22R (V1 146 kn, VR 153 kn, and V2 164 kn).

The aircraft lifted off near the end of the runway. The landing gear struck several fixed structures associated with navigational aids beyond the runway, which were less than 5 feet above the runway elevation. The captain and first officer did not recall striking anything, but the flight engineer recalled feeling and hearing "thumps" after liftoff.

At an altitude of 5,000 feet, the flight engineer reported that the aircraft was not pressurizing. The crew reported their difficulties to air traffic control and eventually diverted to Miami International Airport. After daylight, the flight made a low approach past the Miami tower, and controllers advised that one inboard tire was flat on each main landing gear. The flight dumped excess fuel and landed safely, though additional tires blew out during the landing.

### What the investigation found

The Board concluded that the aircraft's powerplants, airframe, and systems were not factors in the accident. The flight data recorder indicated that the airplane accelerated as expected and became airborne within the confines of the runway, lifting off after a roll of approximately 7,500 feet. However, the Board believed the airplane was being rotated to the climb attitude when it struck the structures beyond the runway's end.

The investigation found that the aircraft's takeoff weight was 33,019 pounds over the maximum weight allowed for a takeoff on runway 22L. The Board noted that the captain and first officer were remiss in their duties for failing to determine if the aircraft could be operated safely from the shorter runway. The Runway Analysis Manual would have indicated the weight restriction, and the radio transmission from the other pilot should have alerted the crew to the need to consult the manual.

### Probable cause

The National Transportation Safety Board determined that the probable cause of the accident was "the captain's decision to use a runway that was too short for the aircraft's takeoff performance capability under existing load and weather conditions. As a result, the aircraft struck obstacles beyond the departure end of the runway before it began to climb. The flightcrew had failed to use available data which would have informed them that the runway was not long enough for the takeoff."