HAARP test with Cold Bay receivers detected aircraft beyond line of sight, military says

Alaskan Command and its partners detected aircraft over the Gulf of Alaska and Bering Sea beyond line of sight during live-fly testing Sept. 7-11, according to a military release issued Monday. The tests paired the University of Alaska Fairbanks' High Frequency Active Auroral Research Program facility near Gakona, known as HAARP, with a low-cost receiver array in Cold Bay.

The experiment examined whether an existing high-frequency transmitter, paired with a newly developed receiver array, could detect aircraft beyond the coverage of current long-range radar sites. The release cites Alaska's vast distances, harsh weather and limited infrastructure as obstacles to air surveillance. It describes the results as skywave, or beyond-line-of-sight, detections. It does not say whether any detected aircraft were beyond the reach of existing radar.

"Understanding what this technology can do in the Arctic starts with collecting data under real operating conditions," said Dr. Carolyn Stwertka, chief scientist for Alaskan Command. Working with operational units, she said, lets researchers compare the experimental observations with known aircraft positions and assess where the approach could help fill gaps in air surveillance.

Those known positions came from cooperative flights: an E-3 Sentry from the 962nd Airborne Air Control Squadron, HC-130J Combat King IIs from the 211th Rescue Squadron and KC-135 Stratotankers from the 168th Air Refueling Wing. Initial results show detections correlated with these "truth flights," and the team met or exceeded its test objectives, according to the release. Data analysis continues.

MITRE developed the Cold Bay array and designed and executed the field experiment. U.S. Northern Command, the Air Force Research Laboratory and Defence Research and Development Canada also took part. The September test was the last live-fly event in a three-year series.

At a June 9 hearing of the U.S. Senate Appropriations Subcommittee on Defense, U.S. Sen. Lisa Murkowski said better understanding gaps in surveillance would have to be a priority. Alaska News reported Aug. 14 on the Air Force's need to inspect four Cold War-era Arctic radar towers, 1950s sites that still watch Alaska's skies.

Alaskan Command says the work supports a broader push to strengthen Arctic defenses, and that better detection and tracking across Alaska and its approaches helps commanders assess potential threats.