Losing a modern, intercontinental jetliner with more than 200 people on board – still missing without even a trace of wreckage after more than two months of costly search efforts – is both bizarre and unprecedented.
The mystery of the vanished Malaysia Airlines Flight 370 has prompted the United Nation's Montreal-based aviation agency to announce it will pursue new standards for global tracking of flights.
"The industry is absolutely in solidarity about putting in place global tracking," Nancy Graham, director of the International Civil Aviation Organization's Air Navigation Bureau, said at an ICAO conference Tuesday.
However, the costs and complexity of tracking more than 36 million flights every year remain daunting, especially given that the greater threat of fire requires that pilots can isolate or turn off any electrical system on board.
Over land and close to coasts where radar coverage is effective, commercial flights are tracked continuously by so-called "transponders" – devices that when interrogated by special radars return flight information that can be monitored by air-traffic controllers.
But investigators believe someone in the cockpit of the Beijing-bound Malaysian jet deliberately turned off several of its systems – including the transponder, which transmits flight identification, position, course, speed and altitude, as well as a satellite reporting system for engine and maintenance issues.
That occurred shortly after a routine radio call when one of the pilots reported to air-traffic controllers that the flight was leaving Malaysian-controlled airspace about an hour after takeoff from Kuala Lumpur.
"In a world where our every move seems to be tracked, there is disbelief both that an aircraft could simply disappear and that the black box is so difficult to find," said Tony Tyler, director-general of the International Air Transport Association, the trade group for the world's airlines and one of the groups at the Montreal conference.
"Some progress" has been made since the crash of an Air France flight over the Atlantic five years ago, he said. That jet's disappearance wasn't noticed for several hours. But, Mr. Tyler added, "We must accelerate our efforts. We cannot have another aircraft simply disappear."
In the Air France crash, routine satellite reporting continued until six minutes before impact but it still took two years to find the flight data and cockpit recorders which showed that the pilots had lost control of a perfectly flyable aircraft after the autopilot switched off.
ICAO only proposes standards. Member countries impose and enforce regulations. So it could be years before global tracking becomes a reality. Most major airlines already pay for routine satellite reporting of systems, although there is no requirement.
A task force will examine nearly two dozen proposals from satellite and other communications companies before the ICAO begins works on defining an international standard for global monitoring.
Although most aircraft flying oceanic routes are already tracked by one of the various commercial satellite services, there is no international standard. The flight crew, however, can turn off most of those systems, usually to isolate and shut down circuits in case of fire.
Part of the challenge facing ICAO and national regulators will be devising a system that can't be disabled while posing no fire threat if there is a malfunction.
Paying for real-time, constant monitoring of millions of flights using scarce and expensive satellite services will add significant costs.
Among the solutions under consideration are ones that would allow regular reporting – perhaps as often as once a minute – of an aircraft's position, altitude, speed and course, recorded and transmitted via satellite. Special alerts would be sent if a sudden or unexpected change occurred or if an aircraft suddenly went silent.
Inmarsat, the British-based satellite provider, which provided forensic work on hourly "handshakes" from Flight 370 to help determine possible flight paths, already offers basic flight tracking free to airliners.
"ICAO will continue to provide the necessary leadership to ensure all issues are considered expeditiously," said the UN agency's president, Olumuyiwa Benard Aliu.
However, he added: "ICAO will not be endorsing any particular solution."