Houston air traffic controllers are now using Automatic Dependent Surveillance-Broadcast (ADS-B), a GPS-based, NextGen technology, to separate and monitor aircraft flying over the Gulf of Mexico.

That milestone, announced Tuesday by FAA Administrator Randy Babbitt, came as the U.S. Coast Guard prepared to shut down the U.S. Loran-C chains that for decades provided long-range position-fixing capability to mariners and aviators.

“This is a significant, early step toward NextGen,” said Babbitt at the Houston Air Route Traffic Control Center. “We’re delivering on time a system that’s not only more accurate than radar but comes with significant safety and efficiency benefits. This will save time and money for aircraft operators and passengers and reduce our carbon footprint.”

Previously, there was virtually no radar coverage over the Gulf, which required 120-mile in-trail separation of high-altitude IFR traffic.

Similarly, individual helicopters flying under IFR at low altitudes to and from oil platforms were encased in 20x20-mile “boxes” to ensure safe separation from other helicopters. ADS-B now permits five-mile separation.

ADS-B-equipped aircraft use GPS to determine their position, and broadcast it (the B in ADS-B) to ATC ground stations. The ground stations relay the aircraft identity and position to controllers’ displays where it can be fused with radar data as appropriate.