So how might they be upgraded? “Both airliners and black boxes could be fitted with state-of-the-art detachable (or jettisonable) transmitters that...allow their position to be pin-pointed within a few metres,” says Beaver. “The beacons would be positioned on and around the tail as this is the part of the airliner most likely to survive the impact. Using accelerometers, one or two would break off and there would be another, which is crew-released. A similar technology is used for deep-diving nuclear-powered submarines. Batteries could be sea-water powered, solar powered or have long life lithium cells.”

Other tweaks could improve the battery life, says Mischa Dohler, professor at King’s College London and cofounder of Worldsensing, a sensor company. “An important but fairly simple change would be to have the black box emit the sonar location pulse not as often as every second; if you have it send one pulse every 10 seconds, we could extend the lifetime to almost one year instead of one month – a much larger window to find the black box.

Cockpit broadcasting

“Current aeroplanes make several different kinds of services available to passengers: interactive media, movies, games, music, internet. You can also make satellite calls from your seat,” explains David Cenciotti of aviation news website TheAviationist.com. “This means that airliners are always interconnected in some way. Why not use one of these channels to report the CVR (Cockpit Voice Recorder) and FDR (Flight Data Recorder) position in real time?”

Cenciotti concedes that this could be costly however, because satellite bandwidth is expensive. A better idea might be…



‘Triggered transmission’

What does this mean? It’s a proposed technique for monitoring and locating aircraft that arose in the wake of Air France Flight 447, the Airbus A330 that crashed into the Atlantic Ocean in 2009, explains Matthew Greaves, head of the Safety and Accident Investigation Centre at Cranfield University in the UK. “Floating wreckage was found within the first few days, but it still took two years to locate the main wreckage on the sea bed,” he says.

The BEA – the French national air crash investigation agency – set up a working group to investigate what could be done to help locate wreckage in future accidents. They recommended triggered transmission, which only broadcasts an alert when something out of the ordinary happens.“It monitors flight parameters such as height, speed, pitch, roll, and so on,” explains Greaves. “It aims to identify when something unusual is happening which might be an accident. The system then sends an alert signal that is picked up on the ground.”