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The Coast Guard is evaluating technologies that would allow unmanned aircraft systems (UAS) to operate beyond an operator’s line of sight to clear airspace, enabling the systems to operate at longer ranges and eliminating the need for someone to keep the UAS clear of other aircraft.
Last August, the Coast Guard Research and Development Center evaluated detect and avoid technology called Passive Acoustic Non-Cooperative Aircraft Collision Avoidance (PANCAS) on an AeroVironment [AVAV] small catapult-launched Puma UAS to see how far out the system could detect other aircraft. This technology would allow UAS operators to avoid other aircraft.
The PANCAS system, which relies on passively listening for the acoustic signature of other aircraft that a UAS equipped with the system can avoid them, has a 360-degree listening range. The Coast Guard said that other sense and avoid technologies that use active transmitters may not provide the same all-around view and may require more of a UAS’s limited power supply.
The Coast Guard this week said the “PANCAS evaluation was very successful” but the technology isn’t ready for approval by the Federal Aviation Administration. The service said waterproofing of the technology to allow it to land in water needs to be done.
The PANCAS technology was developed by Scientific Applications & Research Associates, Inc.
Last November, the Research and Development Center also used a long-range directional antenna aboard a Coast Guard small boat to conduct beyond visual line of sight (BVLOS) operations with a Puma UAS, extending the range of the unmanned system out to 31 nautical miles. The service said it used two ground control stations for the evaluation, one at Air Station Cape Cod in Massachusetts and the other on a response boat from Coast Guard Station Cape Cod Canal.
As with the PANCAS system, the antenna-based detect and avoid evaluation was also “successful and proved the antenna’s viability for ground-based operations,” the Coast Guard said. It added that “The demonstration also validated the need for a 360-degree directional antenna for BVLOS operations by the Coast Guard boating community.”
The Coast Guard’s small boats don’t have flight decks, so the ability to operate UAS at BVLOS ranges could offer these vessels a force multiplier capability by extending their range for intelligence, surveillance and reconnaissance gathering.
“The ultimate goal of this project is to provide a pathway for UAS to operate BVLOS for both flight deck-equipped cutters and smaller vessels without a flight deck, providing a tool to increase mission effectiveness for Coast Guard surface operations,” Steve Dunn, a researcher with the Research and Development Center’s Aviation Branch, said in a statement.
The center is planning additional evaluations of radar, visual and acoustic systems aboard UAS with future evaluations focused on a long-endurance aircraft capable of operating for nearly seven hours for support of vessels without flight deck, and aboard vertical take-off and landing aircraft for operations aboard cutters with flight decks. The evaluations are planned through early 2023.
The Coast Guard said the goal in both upcoming efforts it to obtain an FAA Certificate of Operations to used the sense and avoid technologies for BVLOS operations.
