Bell/Agusta civil tiltrotor returns to flight status
After a hiatus of more than two years, the Bell/Agusta BA609 civil tiltrotor returned to flight status on June 3, flying for 1.3 hours. The aircraft, S/N001 and the only BA609 to fly to date, last flew on April 14, 2003, after accumulating 14 flight hours from the time of its first flight on March 7 of that year. It also logged some 41 ground test hours.
Plans announced before the first flight called for a near-total teardown of the first flight-test prototype following what was expected to be that aircraft’s first 20 flight hours of function-and-reliability tests. Several months were expected to go by before the test program was to resume. As it turned out, the aircraft managed to complete its flight-test goals in only 14 hours, and Bell/Agusta estimated it would be back in the air in July 2004.
Those initial flight hours were all accomplished in helicopter mode, with the prop-rotor nacelles tilted forward to 75 degrees and aft to 95 degrees (90 degrees indicating the prop-rotors are horizontal). Most of the flying was in a hover, though the test pilots took the aircraft up to 120 knots.
During its June 3 return-to-flight, test pilots Roy Hopkins and Pietro Venanzi flew S/N001 in hover mode around the pattern at Arlington Municipal Airport in Texas, attaining a top speed of 86 knots with the nacelles tilted forward to 75 degrees. They also hovered the aircraft forward, sideways and backwards.
Full conversion to airplane mode (zero-degree forward tilt) is the next big goal for the BA609 and Bell/Agusta engineers and test pilots hope to achieve this later this month. The success of the June 3 flight, said Jack Gallagher, program director, “clearly demonstrated we are ready for full tilt on the 609.”
Meanwhile, the number-two aircraft, now undergoing tests in support of S/N001 at Agusta’s assembly and flight-test facility in Italy, is expected to make its first flight in the fourth quarter. Bell plans to ship BA609 S/N003 to Italy later this year. A total of four prototype 609s will eventually fly the program required for FAA and EASA certification, a moving target now planned for 2008, with initial deliveries to follow soon after. Bell/Agusta reports holding enough firm orders for the 609–about 60–to commit “more than the first two years of production.” Several years ago, the company gave the price for the first tranche of aircraft ordered as about $10 million, and said later it would adjust the price for subsequent orders when it could better determine the 609’s production costs.
Like the V-22, its much larger, military cousin, the six- to nine-passenger BA609 is a digital, fly-by-wire tiltrotor. Together they represent Bell’s and AgustaWestland’s first foray into production fly-by-wire rotorcraft and, indeed, are among a small handful of fly-by-wire rotary-wing designs to make it past the experimental stage worldwide–two notable examples being the NH Industries NH90 and Kazan Ansat.
BA609 preliminary performance numbers include a 275-knot cruise speed, maximum unrefueled range of 700 nm, maximum takeoff weight of 16,800 pounds and a ceiling of 25,000 feet. The pressurized civil tiltrotor will have a three-screen Collins ProLine 21 cockpit and eventually be certified for IFR flight into known icing conditions.