Overrun 767 crossed threshold at twice normal height before touching down long

Preliminary analysis suggests 21 Air twinjet landed halfway down Miami runway before fatally colliding with van on perimeter road.
US investigators have disclosed that the 21 Air Boeing 767-300 freighter which fatally overran at Miami crossed the runway 30 threshold at 105ft – twice the typical height.

It touched down 3,750ft beyond the threshold, according to preliminary information from the National Transportation Safety Board which is probing the 6 September accident.

Runway 30 has a length of 9,360ft but this includes a threshold which is displaced by 945ft, which suggests the aircraft landed halfway down the runway.

It was travelling at a groundspeed of 160kt on touchdown, which occurred 13s after passing the threshold.

But the aircraft did not immediately settle. The weight-on-wheels sensor switched “intermittently” between ‘air’ and ‘ground’ for about 7s, says the inquiry.

By the time the aircraft achieved stable ‘ground’ status from the sensor, it had 2,730ft of runway remaining.

Flight-data recorder information shows the speedbrakes remained stowed – there was no change in the position of the speedbrake handle – and the thrust-reversers did not deploy.

The inquiry has yet to confirm the effects of the alternating air-ground status on the aircraft’s systems.

It says the wheel brakes were manually applied at 146kt groundspeed but the brake pedals were released 8s later at 120kt, when the thrust levers were advanced to go-around power with 930ft of runway left.

Recorded data indicates that the flaps, which had been set to 30° about 10s before touchdown, started retracting to 25°.

Four seconds later, at 117kt, the thrust levers were then retarded to idle and brakes were re-applied. But only 415ft of runway remained at this point and the jet overran at 113kt.

It collided with the localiser and approach lighting system at the far end of the runway, travelling 1,200ft beyond the paved surface during which it struck a van with seven occupants on the perimeter road, fatally injuring five of them.

The aircraft crashed through a perimeter fence and crossed a highway, hitting a sports utility vehicle and seriously injuring its sole occupant before coming to rest adjacent to a parking lot.

Both pilots, the only people on board the jet, escaped with minor injuries.

According to the safety board, the captain – who was flying – had been type-rated on the 767 for about four months before the accident.

He had accumulated about 150h on the model during the five months since he was hired by 21 Air. The first officer had held a 767 rating for longer, about 17 months, and had 800h on type.

The aircraft had been operating a service from San Juan on behalf of retailer Amazon.

Investigators have yet to reach conclusions over the occurrence, but state that the analysis will include an aircraft performance study to “refine” the sequence of events and asses the physical state of the aircraft during its approach and landing.

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