BAE Systems is proposing fitting production Herti unmanned air vehicles with a combined radar and electro-optic sense-and-avoid system to allow for operations in non-segregated airspace.
The nose-mounted radar would actively monitor airspace ahead of the aircraft, while the electro-optic system would operate in a passive mode. The passive system could be developed either as an adaptation of the main electro-optic surveillance suite – which comprises two fixed staring wide field-of-view cameras and a turret-mounted narrow field system, or the existing forward-facing pilot camera. The passive system would use optical detection algorithms analysing data in real time to identify potential collision threats.
Martin Rowe-Willcocks, BAE business development executive for military autonomous systems, says prototype electro-optic sense-and-avoid suite elements was test flown earlier this year aboard the company’s own BAe Jetstream 31 twin-turboprop.
Studies on appropriate radar options are continuing, but one approach may be to adapt the Selex PicoSAR miniature synthetic-aperture radar, he says. PicoSAR has already been identified as a potential element of the Herti ground surveillance sensor suite.
Planning for sense-and-avoid suite capabilities includes ensuring that the UAV would respond in identical ways to a manned aircraft, with other pilots needing to be able to safely predict its behaviour, he says.
The final suite configuration will depend on the development of standardised sense-and- avoid requirements for UAVs by regulators. Airworthiness certification is also being pursued, with policy developments in this area being closely monitored as the programme advances. “This will be a fully cleared vehicle,” says Andrew Wilson, BAE director of autonomous airborne system sales. “We will clear it to aircraft standard.”
Automated airspace deconfliction functions have already been integrated into the existing Herti ground-control system as part of the flight-control and navigation subsystems.
That capability has been tested at BAE’s Warton plant, Rowe-Willcocks says, using real world data fed into the ground-control system via a TCAS-B terminal, with this then supporting simulated Herti missions in a variety of UK airspace environments.
Other trials have seen the Herti ground-control system linked with a Eurofighter EF2000 Typhoon simulator at Wharton. Operators of both systems attempted to create collision situations. The Herti repeatedly identified the looming accident and took evasive action, say Rowe-Willcocks.