Paris Air Show

Deployable Black Box Should Be Easier To Locate

 - June 17, 2017, 5:08 AM

Airbus said last week that it is developing new automatic deployable (ejectable) flight recorders, which it suggests could be fitted from in 2019 on new airliners. Having introduced the project at the company's Safety Day last Thursday, it indicated that it may hold a further briefing–and possibly even launch development–at the Paris Air Show, which starts on Monday.

The European airframer has partnered with U.S. company L3 Com to design the system, which will include two recorder units (each including a flight data recorder and a voice recorder). One unit would be installed in the front of the aircraft, while the second one would be ejectable from the tail, with a spring system and CO2 cartridge. The ejection would deploy if sensors detected airframe deformation or water immersion. Airbus explored a rocket-fired solution but rejected it as too dangerous. A retrofit for existing aircraft will be possible but extremely expensive, said Airbus.

With this new system, the ejected recorders would float on the surface with a ULB broadcasting for 90 days, per new ICAO rules starting from January 2018. This ULB will also broadcast in low frequencies (8.8 kHz) with a range of 22 km (14 miles) compared with the five km (three miles) of previous systems.

During a media briefing a few days before the opening of the 2017 Paris Air Show, Airbus discussed the issues of aircraft tracking and locating flight data recorders and cockpit voice recorders after a crash, especially involving overwater flights. Everyone recalls the two-year search for the “black boxes” in the Air France AF447 accident and the disappearance of Malaysia Airlines Flight MH370, on a flight from Djakarta to Beijing, for which voice and cockpit recorders have still yet to be found.

There have been 42 over-ocean accidents in the past 20 years. The main issue is always finding the site of the wreck and the recorders. The ULB (Underwater Locator Beacon) attached to current recorders broadcasts for only 30 days, far less time than has shown to be needed for search and rescue teams, especially when the debris lies 3,000 meters or more below the surface of the ocean. “Salinity in the water prevents hearing the pings below 2,000 meters [6,500 feet] depth,” said Géraldine Vallée, Airbus director of flight safety.

Regarding flight tracking, even aircraft equipped with the ADS-B have almost no coverage over deserts, polar zones and near the middle of oceans. And with ELTs (Emergency Locator Transmitters) Vallée said, “In most accidents, the ELT doesn’t trigger, and there’s no transmission from under water.” 

According to Airbus, this problem will be partly solved with new satellite constellations (Iridium Next, for example) which will have a far better coverage around the globe. The European airframer proposes an ELT improvement with a second generation equipped with an integrated GPS unit and a transmitter broadcasting a signal within five seconds after a dangerous situation is detected.