DARPA down-selects six for Ph.1b of ANCILLARY program

The US Defense Advanced research Projects Agency, DARPA, has down-selected six companies from the original nine contenders who will advanced to the next stage of its ANCILLARY program.

Phase 1b of ANCILLARY, which stands for AdvaNced aircraft Infrastructure-Less Launch And RecoverY, will see Sikorsky, Karem Aircraft, Griffon Aerospace, Method Aeronautics, AeroVironment and Northrop Grumman progress to the 10-month design phase for their proposed autonomous Uncrewed Air Systems (UAS).

The UASs are intended to be Vertical Take-Off and Landing (VTOL) demonstrators. The DARPA ANCILLARY program, launched in 2022, aims to develop and demonstrate an X-plane with the critical technologies required for a leap-ahead in long endurance, Class 3 VTOL UAS performance, says Northrop Grumman.

The autonomous UAS would be able to launch and recover from ship flight decks and small austere land locations in adverse weather without additional infrastructure equipment, thus enabling expeditionary deployments and locally commanded responsive intelligence, surveillance, reconnaissance and targeting (ISR/T) with unique payload capabilities. Unlike large VTOL systems, the small UAS size would allow many aircraft to be stored and operated from one ship, creating a tactical beyond-line-of-sight, multi-intelligence sensor network capability.

Northrop Grumman is a leader in development of autonomous UASs and long-endurance aircraft, including the MQ-4C Triton and MQ-8 Fire Scout. In this phase the company will lead a team, including Leigh Aerosystems and Near Earth Autonomy, to transition what it calls an affordable near-term capability to the warfighter community.

Sikorsky, meanwhile, is conducting flight tests to mature the control laws and aerodynamics of a novel VTOL UAS. The flight tests are intended to prove the efficiency and scalability of a twin proprotor ‘rotor blown wing’ configuration that sits on its tail to take-off and land like a helicopter and transitions easily to horizontal forward flight for long-endurance missions, such as Intelligence, Surveillance, Reconnaissance and Targeting (ISR&T).

The term ‘rotor blown wing’ refers to the constant airflow from the proprotor wash across the wing. Sikorsky chose the design to reduce drag on the wing in hover mode and when transitioning to forward flight, and to increase cruise efficiencies and endurance.

“Flight tests are underway to verify our tail-sitting rotor blown wing UAS can launch and land vertically with high stability, and cruise efficiently on wing,” said Igor Cherepinsky, director of rapid prototyping at Sikorsky Innovations. “Key enablers to flight maneuverability, and future vehicle scalability, are our MATRIX autonomy flight control system, and an articulated rotor system similar to those in traditional helicopters.”

For the flight tests now underway, Sikorsky is flying a proof-of-concept vehicle powered by a battery. If selected to produce an air vehicle for a future ANCILLARY phase, Sikorsky plans to build a 300-pound hybrid-electric version to include a 60-pound ISR payload.

Australian firms are already working towards similar goals. At last year’s Avalon Air Show in Melbourne BAE Systems Australia launched its STRIX VTOL UAS which is designed to carry a 160kg ISR or kinetic payload up to 800km. It can also act as a ‘loyal wingman’ to helicopters. The company also launched at Avalon the RAZER low-cost guided munition which could arm the STRIX.