PARIS - A company establishing a global commercial aircraft-tracking service says it will offer a piece of that capability free-of-charge to all airlines equipped with automatic dependent surveillance-broadcast (ADS-B) terminals.

The company, Aireon LLC of McLean, Virginia, a joint venture between Iridium and air navigation service authorities in Canada and Europe, said Sept. 22 it would offer free ADS-B tracking as an emergency service available to all certified air regulators and search-and-rescue authorities, regardless of whether they subscribe to Aireon's fee-based commercial aircraft-surveillance offering.

Known as Aircraft Locating and Emergency Response (ALERT), the system will use already-mandated ADS-B equipment on commercial Airbus and Boeing aircraft, requiring no additional investment on the part of airlines or air navigation safety providers in equipment or services.

“We built the system for real-time surveillance of aircraft for efficiency improvements, not to find the occasional missing aircraft,” Aireon President and CEO Don Thoma said in an interview. “But given that most aircraft in the world will be equipped with ADS-B, including a large percentage that will be equipped even by 2018, we will have a capability that will be collecting the location information on aircraft around the globe.”

Thoma says the company plans to develop an ALERT application that will allow registered users to create an authentication process that enables them to log-in and query the last known location and flight track of an aircraft, so long as the ADS-B system is operational.

“For those organizations that don't do it that way, there'll be a 24/7 call center that can get that information to them,” he said.

Aireon's ADS-B terminals are being fitted onto the second generation of Iridium's 66-satellite mobile services constellation scheduled to enter service in 2017. Rival Inmarsat of London, whose satellite fleet also offers global coverage, except for the polar regions, said recently it would offer a similar service to airlines. Globalstar of Covington, Louisiana, is also working on an ADS-B service using its second-generation satellite constellation.

Next year, at a meeting of the International Telecommunications Union (ITU), the U.N. regulator of wireless spectrum is expected to consider an extension of the current radio frequency allocation reserved for air-to-ground ADS-B communications to include space-based ADS-B. Despite opposition from the European Satellite Operators Association to the extension, Aireon's ALERT proposal could give ITU regulators the impetus necessary to add satellite links to the existing spectrum allocation for ground-based ADS-B.

In the meatime, Aireon says it plans to engage aviation stakeholders over the next 12 months “to define the technical, operational and legal details of providing this service in emergency situations.”