Australian officials have acknowledged the potential weakness of deliberate disconnection while detailing an upcoming aircraft tracking trial programme.
The programme – based on automatic dependent surveillance contract (ADS-C) technology – aims to test short-interval tracking capability, following the loss of Malaysia Airlines flight MH370.
But air navigation authority Airservices chair Angus Houston, in a briefing on the initiative, cautioned that it would not necessarily have assisted in the case of the missing Boeing 777, given the possibility that several transmitters were disengaged during MH370’s disappearance.
“I think we’ve got to be very, very careful – because you can turn this system off,” he says. “While the system was operating we’d know exactly where the aircraft was.
“But if somebody had turned the system off…we’re in the same set of circumstances as we’ve experienced on the latter part of the flight of MH370.”
ICAO is formally recommending that aircraft be tracked at 15min intervals. Houston says the tracking test will probably use a 14min spacing, which will shorten – to around 5min or even less – in the event of an unexpected deviation.
Deviation would involve a 200ft change from the assigned altitude or 2nm shift from the expected track, he states.
“[This] obviously means we’re going to be in a much better position, not only to track the aircraft but, if something goes wrong, to provide the necessary information to the search and rescue authority as to where the best place to start the search is,” he adds.
But Houston says the tracking capability is “not a silver bullet” and that the crucial aspect of disconnection has yet to be fully addressed.
“This is one of the arguments that is put forward…if there this an electrical problem, which results in smoke – or, even worse, fire – you need to be able to isolate the electrical systems that are affected,” he states.
“This is something that needs to be looked at and discussed very carefully before any decisions are made.”
Airservices will initially host the tracking trial at its Brisbane centre. It is to hold discussions with air traffic control counterparts in Indonesia and Malaysia, within the next couple of weeks, to extend the programme to both countries.