Alvorlig bakkeuhell - Hva førte egentlig til dette? - Curt Lewis

ATR tow-tractor driver tried to avert Jakarta 737 collision

Preliminary analysis of the take-off collision at Jakarta's Halim Perdanakusuma airport indicates that the tractor driver moving an ATR 42-600 attempted to avert an impact.

The driver saw the approaching Batik Air Boeing 737-800 as it was rolling for take-off on runway 24, according to French investigation authority BEA, citing initial information from Indonesian counterparts.

BEA says that the driver had requested clearance to tow the TransNusa Air Services ATR from the north apron to the south apron, which required crossing runway 06/24.

Air traffic control instructed the tow to proceed via taxiway C, across the runway, and onto taxiway G to the south apron.

The crew of the 737 had requested taxi clearance to runway 24 via taxiway C at 19:50 local time.

BEA says the 737 was told to taxi first, ahead of the towed ATR.

It states that, after entering the runway, the tractor driver saw the 737 conducting its take-off roll, and adds: "The [driver] tried to swerve the [vehicle] direction to the right to [the] runway shoulder."

But the avoiding manoeuvre could not prevent the collision and the 737's left wing-tip struck the vertical fin of the ATR as well as its left wing.

The 737 crew aborted the take-off and came to a halt on the runway about 400m (1,300ft) from the point of impact.

Both aircraft were badly damaged during the 4 April accident, although none of those on board was injured.

BEA has not specified the radio frequencies used by the tow tractor driver and the crew of the 737 during their communications with air traffic control.

Neither has it detailed the specific clearance instructions given to the 737, although Batik Air has previously claimed that the jet had been "released" for take-off, nor whether the towing clearance contained any proviso regarding entering the runway.