The jet operated by Malaysia Airlines with 239 people on board disappeared from radar less than an hour after takeoff from Kuala Lumpur on March 8 en route to Beijing and despite many days, has yet to be located.
Industry groups have for some years been looking at various options to ensure that while in flight, people on the ground know exactly where an aircraft is, how the aircraft is performing and in the event of an accident help investigators rescue survivors and track the wreckage.
Those options feature automatic regular updates of an aircraft’s location throughout its flight, the triggered relay of critical operational data when an aircraft senses it is about to crash and improvements to black box technology to enhance survivability and its ability to be found.
“the conclusion has been that the costs associated with real-time streaming of aircraft data are too expensive for airlines or air traffic control authorities”
“Sending continuous data for all flights would create a huge amount of data and might get very difficult to monitor and analyse,” admits Tony Tyler, director general of the International Air Transport Association, who says the airline industry body is planning to consult aircraft manufacturers on increasing the use of real-time data transmissions.
Following the 2009 Air France Flight 447 Rio-Paris air tragedy, French air accident investigators recommended that today’s digital datalink technology that replaces VHF voice communications is supplemented by mandatory real-time speed, altitude and location transmissions.
But as IATA’s Tyler rightly points out datastreaming of continuous flight data remains unfeasible for most airlines due to cost. Involved in several studies on streaming black box data following the terrorist attacks of 9/11 and Flight 447, global satellite communications provider, Iridium Communications supports that view.
“Each time, the conclusion has been that the costs associated with real-time streaming of aircraft data are too expensive for airlines or air traffic control authorities,” says Don Thoma who heads Iridium’s Aireon business.
There is however the prospect of far greater surveillance capability through multi-billion dollar air traffic modernisation efforts called NextGen and SESAR on both sides of the Atlantic. Airlines in both the United States and Europe will soon be mandated to equip their aircraft with ADS-B transponders that will report their location to air traffic control through a corresponding ground-based network. Airspace coverage over remote terrain and the high seas remains problematic, however.
Iridium’s space-based Aireon venture plans to solve the shortcomings of that surveillance capability on a global scale specifically over oceans or remote areas and, because airlines are already upgrading with the necessary Automatic Dependent Surveillance Broadcast (ADS-B) kit as part of modernisation mandates, Aireon plans to leverage that investment spend through offering the future service on a subscription basis. ADS-B information such as location, velocity and ICAO number – available in near real-time – could prove invaluable in providing a greater awareness of an aircraft’s location anywhere in the world.
Luxemburg’s SES TechCom also signed a long term agreement with strategic partners German Aerospace Center and Thales Alenia Space Germany last year to develop a European space-based system to monitor and optimise air traffic control using the Proba V satellite.
Search & Rescue
When it becomes available from 2017, Aireon will provide the precise location of any aircraft transmitting an ADS-B signal. Developed with the principal aim of enhancing efficiency in routine airline operations, space-based surveillance also represents a far more cost effective and valuable addition to search and rescue efforts.
“This capability will aid in search and rescue situations, such as Flight 370, in ways that couldn’t be possible through the ground-based infrastructure available today,” says Thoma. “Without a precise location for the last known coordinates of an aircraft, the search area can span hundreds or even thousands of miles. Space-based ADS-B will greatly expedite search and rescue efforts through near-real time location reporting from the aircraft, substantially reducing the time to locate planes that are no longer transmitting ADS-B signals.”
Calgary-based FLYHT Aerospace Solutions has also developed the Automated Flight Information Reporting System (AFIRS) which combines the infrastructure of the internet and the constellation of 66 satellites operated by Virginia-based Iridium Communications.
“understanding the reason for the loss of Flight 370′s transponder signal is becoming a critical aspect to understanding the fate of the missing aircraft”
Here, when an aircraft senses an adverse event, AFIRS can send streaming data off the aircraft to one of Iridium’s 66 satellites and then down to ground-based servers, where the message is interpreted and sent to the airline.
Even so, understanding the reason for the loss of Flight 370′s transponder signal is becoming a critical aspect to understanding the fate of the missing aircraft. It’s rare for a pilot to intentionally turn off a transponder during flight, but occasionally there is a legitimate reason, such as a malfunction, electrical short or where there is a risk of fire spreading.
Rudy Kellar is executive vice president at Nav Canada which is a principal investor and future customer of Aireon. It already operates an advanced ground-based ADS-B network in remote terrain and now wants to extend its surveillance capability even further over oceanic and polar airspace. He says Aireon will be of significant assistance to the Canadian air navigation service provider as it allows the second-by-second monitoring of aircraft positions and could usefully support search and rescue efforts.
“In Canada, we use this aircraft location information to support our Canadian Search and Rescue which is provided by the Department of National Defence. Pilots flying in airspace that is mandated ADS-B would normally be identified with their transponder on and required to maintain it on in that airspace,” says Kellar
The fact remains that the pilot today has the ability to turn an ADS-B transponder off which disables the surveillance technology. “If this transponder is turned off, we would no longer receive position reports,” Kellar points out.
Ed Sims is the chief executive of Airways New Zealand and he questions whether full Aireon-type surveillance would have stopped Flight 370 from disappearing.
“If – and everything is a big if still – the transponders were turned off,” says Sims, “even satellite ADS-B still relies on receiving a signal. If an aircraft could fly over an hour without transmitting even though it appears to have registered on military primary radar, it’s not clear whether a satellite would have initiated a more immediate response from authorities. Aireon would however almost certainly help in more immediate location through more precise area surveillance.”
Mary Kirby, editor of Runway Girl Network reports that satellite operator Inmarsat is prepared to support a ‘global aero distress’ service based on its existing maritime service which crucially could not be simply switched off in the cockpit. The UK business which has provided essential assistance to the MH370 investigation, says this distress service could be implemented in a fast and cost efficient way, using hardware already installed on some 15,000 aircraft in the world fleet.