AgustaWestland AW609 test pilots Dan Wells and Paul Edwards insist that the civil tiltrotor is “easy to fly” for those transitioning from either helicopters or fixed-wing aircraft. The duo brought AW609 test ship number one to Heli-Expo from the manufacturer's 609 test facility in Arlington, Texas. Along the way they flew up to 23,000 feet and saw average fuel burns of 1,000 pph.
Wells joined the program three and a half years ago after serving as a U.S. Army test pilot and being seconded to the Air Force to fly its version of the military V-22 tiltrotor, the CV-22, test flying avionics packages. After serving in the Army for 26 years, he joined Bell Helicopter and then AgustaWestland when Bell sold its share of the 609 program to the Italian manufacturer. Wells has logged 650 hours in tiltrotors.
Edwards flew rotorcraft as a test pilot for the UK Royal Navy and was seconded to the U.S. Navy as a rotary wing test pilot. He has both rotary wing and fixed-wing aircraft experience. He joined the 609 program in 2013 and has 300 hours in the tiltrotor.
Edwards said the hardest thing about flying the 609 is to keep in the proper mindset given the aircraft's profile. “It changes from a fixed-wing aircraft to a helicopter in about 30 seconds. So you have to fly it like a fixed-wing when it is fixed-wing and then get ready to fly it like a helicopter. It sounds trite, but that is what it is like.
“The fly-by-wire system makes it very easy to fly," Edwards added. “Dan and I also are both instructor pilots. When you transition from helicopter to fixed-wing you do have to increase alpha a little to get wing lift. A helicopter is designed for zero alpha. When you roll on the bank in the helicopter you increase a little collective. In an airplane when you roll on the bank you increase a little bit of alpha and that is exactly what you do with this,” Edwards said. “You just have to remember that when you roll into the turn unless you are in conversion mode, when you have to do a little bit of both.”
Edwards said development of the fly-by-wire system on the aircraft is largely done. “We're down to the minutiae,” he told AIN. “It flies beautifully.”
Flying an approach from fixed-wing configuration at full speed to a vertical landing is a busy event, but the fly-by-wire control system helps lessen the pilot workload. “You pull the power off at 250 knots and it slows down at about 10 knots per second,” Edwards explained. “Once you are below 200 knots, you make the first click on the thumbwheel. That speeds the proprotors up to 100 percent. They’re at 84 percent in level cruise for noise abatement and efficiency. That slows you down some more and in a couple of seconds you’re below 180 knots. One more click and the rotors come back off the stops to 50-percent nacelle. Another click and in five seconds you’re doing 80 knots at 75-percent nacelle turning onto final. You can go from 240 knots to 80 knots in about a minute. On short final you're at 82-percent nacelle and about 40 knots. Bring the nacelles back to 95 percent and that will stop you really quickly. You can be on the helipad a minute after you were on the downwind at 240 knots.”
Wells said the 609 really shines on steep approaches. “When you tilt the nacelles back to 95 percent, the fuselage is going to be at about minus seven or eight degrees. You can see exactly where you are going. You can see any obstacles. It is totally different than a helicopter. You'll feel yourself hanging in the shoulder belts. If you are going into an austere environment, that is an amazing ability.”