A ring tail was added and the helicopter drive train modified to accommodate VTDP. Piasecki conducted integrated tests of the modified drivetrain at the Navy's helicopter transmission test facility. The wings were intended to produce lift to offload the rotor so the rotor could be slowed and produce less drag, allowing for higher speed. The cockpit controls were modified with the addition of a manual propeller pitch override on the collective lever for the ring tail. This is the only visible change to the aircraft's existing mechanical controls in the cockpit. The other controls needed to operate the compound helicopter's systems were integrated into the aircraft's existing mechanical controls to reduce pilot workload. The weight added to the X-49A demonstrator aircraft is estimated at due to the requirement to not modify the existing mechanical control system. Operational history The X-49A made its first flight on June 29, 2007 for 15 minutes at Boeing's New Castle County (KILG) flight test center. This flight included hovering, pedal turns, and slow forward and sideways flight using the VTDP for anti-torque, directional and trim control. The X-49A project has been silent since completing its initial testing phase in 2008, with over 80 flight events with and more than 80 total hours logged. Specifications (X-49A) See also References External links Jane's All The World's Aircraft - X-49A "High Speed Helicopter set for first flight in June" article on FlightGlobal.com Rotor and Wing Cover Story Dec 2007 Vertiflite Cover Story Winter 2007 Aerospace Testing International Dec 2007 Boeing Eyes X-49A Technology for Apache Attack Helicopter "Hot-Rod Helicopters". Air & Space magazine, 1 September 2009. Pushing helicopters faster - X-49A - Aviation Week Video Compound helicopters Ducted fan-powered aircraft X-49 Sikorsky aircraft X-49, Sikorsky Piasecki 2000s United States helicopters Twin-turbine helicopters United States military helicopters Aircraft first flown in 2007