Key options in flight tracking

About seven months ago, Malaysian flight MH370 disappeared en route to Beijing from Kuala Lumpur. The best evidence suggests that the plane’s tracking system was disabled and the plane flown along an airway before it turned south and likely crashed in the Indian Ocean. This has been taken to mean that someone with some aviation knowledge deliberately hijacked the plane.

Despite the best efforts of several countries the wreckage of the plane has never been retrieved. More than half a year later not even a seat cushion has washed up ashore. This has fuelled a lot of conspiracy theories. Many people have been unwilling to believe that it is possible for a plane to disappear in the 21st century.

The story has recently been in the news when the well respected CEO of one of the largest airlines in the world once again called for a tracking system that cannot be switched off from the cockpit. As it happens since the incident, several working groups have been trying to come up with solutions to this challenge.

Right now there are already several active means of tracking planes. Secondary radar picks up signals sent from airplane transponders. This is the primary means by which air traffic control manages traffic. National aviation authorities can make this data available to third parties who build flight tracking apps.

Airlines can get direct information about their billion shilling investments via ACARS, Aircraft Communications Addressing and Reporting System. The system can pick up engine status, airplane position among others and send this information to ground.

While these systems can be improved, they work well enough and, more importantly, they exist in the present. So the real issue is simply how to prevent pilots or any unauthorised personnel from switching off these systems. This poses new challenges.

Fires are a major problem in airplanes. A major potential source of these fires are the electrical systems. Aircraft avionics come with several inbuilt systems to protect against short circuits and other failures that pose a risk of fire.

The several kilometres of wiring connecting the various systems are protected by circuit breakers (CBs). Over the lifetime of a plane, vibrations, oil, among other environmental factors, can wear the insulation of wires down which can cause a short circuit.
Part of the procedures for fighting some electrical fires involve pulling out the CBs. Partly for this reason a large number of circuit breakers are located in the cockpit. In order to prevent a pilot from switching off a tracking system, it would be necessary to prevent pilots from being able to access the CBs and thus also removing a means for fighting the electrical fires.

This would also include the CBs for the navigation and communication on which the tracking systems rely on. In short, we would be substituting the risk of a hijacking with an increased risk of fire, both of which are rare.

Dr Ondieki is a pilot with an international airline.