Advanced helicopter rotor systems are to be developed for existing and future US military rotorcraft in the Helicopter Active Control Technology (HACT) programme launched by the US Army late last month.

The US Army says that the overall objective of the project is to develop and demonstrate an active, digital, optical, flight control system integrated with selected mission subsystems to enhance handling qualities and improve mission effectiveness. Preliminary designs for the HACT flight control system will be developed and evaluated during the first phase of the HACT programme. The objective of HACT Phase 2 will be to further develop and incorporate the selected designs into rotorcraft for flight demonstration.

The US Army's Aviation Applied Technology Directorate at Fort Eustis, Virginia, anticipates that up to three firm, fixed price contracts covering 14 months of research work will be awarded under HACT Phase 1.

Only Bell Helicopter, Boeing and Sikorsky Aircraft will be allowed to compete for roles in the two phase HACT research and development project. The US Army says that it limited the competition to the three US aircraft makers because of the extensive amount of related research each firm has performed to date.

The request for proposals (RFP) was released on 20 March with contractor bids due on 20 May.

Research under way for the US Defense Advanced Research Projects Agency's (DARPA) is expected to be applied to the HACT effort. Boeing is already supporting DARPA's work in the fields of smart structures for rotor control and smart material actuated rotor technology blade research.

Applications under scrutiny include embedding "smart material" in rotor blades, which can be controlled by altering the electrical voltage applied to the material. This holds the promise of actively altering blade twist in flight.

The US Army says that the programme will provide for technology insertion into helicopters such as the Boeing Sikorsky RAH-66 Comanche, and future US military rotorcraft such as the Joint Transport Rotorcraft, which will not be available before 2015.

Source: Flight International