October 10, 2012
SYDNEY (AFP) - Australian officials were Wednesday probing how two Qantas passenger jets came to be on a collision course over Darwin last week, reportedly coming within just 250 metres (800 feet) of each other.
The Australian Transport Safety Bureau (ATSB) said it was investigating the incident in which a QantasLink Boeing 717 coming in to land flew close to a Melbourne-bound Qantas Boeing 737 which had just taken off.
"A Boeing 717 inbound to Darwin was cleared to descend through the level of an outbound Boeing 737 near Darwin," the ATSB said.
The bureau said controllers subsequently cancelled the clearance but the two planes had lost separation assurance -- meaning that air traffic control was not effectively monitoring the safe distance between them.
Citing an incident report, Sydney's Daily Telegraph said that an air traffic controller at Darwin airport put the Boeing 717 carrying 115 passengers on a collision course with the Boeing 737 carrying 155 passengers.
Collision avoidance systems on the Boeing 717 detected the error and warned the pilots there was an aircraft just 800 feet (250 metres) below them.
"It passed directly below us. I saw the traffic collision avoidance system display traffic 800 feet below," Captain Robert Flipo wrote in the incident report.
But he added: "It must have been closer than that.
"We had been given a series of nonsensical clearances both lateral and vertical," Flipo wrote, adding that he asked several times about how to approach but received a "non-conclusive response".
Darwin Airport, in northern Australia, is a shared military and public airport and air traffic control is provided by the Royal Australian Air Force.
The Telegraph said the defence department had suspended an air traffic controller over the incident and a full investigation would be carried out.
"An initial defence investigation indicates that an air traffic controller inadvertently directed an arriving and a departing aircraft on a path that would have taken the aircraft through the same height," a spokesman told the paper.
Qantas said it was unable to comment due to the ongoing investigations.
