Bell has begun its US Army Voluntary Flight Demonstrations for the Armed Aerial Scout project using a hybrid Kiowa Warrior.Bell's VFDs began on 22 October and are being conducted at the company's Arlington, Texas facilities using 'Demo 01', an OH-58D rebuilt by Bell from a commercially-purchased OH-58A but featuring the HTS900 engine, Model 407 blades and transmission and the tail rotor from the Model 427.
During the trials, the aircraft will be taken through a series of flight trials by army test pilots working from the ADS-33 handling qualities requirements, the same trials scheme applied to the VFDs of other manufacturers.
'We are offering the army a number of options for our AAS offering building on our long experience with the Kiowa Warrior and our commercial products,' said Mike Miller, director of military business development at Bell.
By offering the use of Model 407 blades and transmissions, the company says it is showing the US Army that it has a roadmap for supplying critical parts and components into the future.
Use of the 407 transmission allows for greater torque loads while the 427 tail rotor gives considerably greater tail rotor authority over the one on the Kiowa Warrior.
Although the VFDs are taking place in Texas, Bell says it has already carried out a series of hot and high flight trials at Alamosa in Colorado using the Demo 01 aircraft. The location - at 7,500 ft above sea level - is used by the army for hot and high training for crews deploying to Afghanistan.
Miller says that despite exploring a number of other Bell helicopter platforms to meet the AAS requirements, including the twin-engine Model 429, the company was satisfied that the single-engined Block II and later a Block III aircraft -which could include the transmission that results from the Future Advanced Rotorcraft Drive System (FARDS) programme - would bring significant cost savings over a twin-engined competitor.
'We asked a not-for-profit independent organisation to examine the cost savings for a single-engine type fleet over a twin-engine fleet over 20 years and it was a saving of $11 billion,' said Miller. 'That was a conservative estimate, but as a taxpayer, I know how I would like the army to spend my money.'
Further advantages would come from being an established type and 'blend seamlessly into the army’s existing supply chains, training programmes and personnel system'.