HAI Convention News

Sikorsky S-76D Demo Flight Proves Performance Boost

 - March 4, 2015, 4:50 PM

With the S-76D certified by the FAA on October 12 last year and by EASA just five days ago, Sikorsky is busily giving demonstration flights in this latest evolution of the popular S-76 at Heli-Expo 2015 this week in Orlando, Fla. AIN was fortunate to have a videographer and this writer–a rated helicopter pilot–on the last flight of 13 sorties on Tuesday.

Raymond Altieri, vice president, COO and one of the founders of Associated Aircraft Group (AAG) of Wappingers Falls, N.Y. flew the demonstration flights. Sikorsky Aircraft bought AAG–which provides charter, aircraft maintenance and fractional ownership–12 years ago, and Altieri has been an employee of Sikorsky since then. With thousands of hours in all S-76 models, the S-92 and Blackhawk, he is also an FAA-designated examiner and provides flight reviews for Sikorsky test pilots.

Customers told Sikorsky they wanted better performance, a quieter aircraft and a better cockpit (less cluttered, more glass) compared with the S-76C++. The company obliged with new Pratt & Whitney Canada PW210S turboshafts providing 1,120 shp for takeoff and redesigned main rotor blades, now all-composite and based on the S-92’s main rotor blades, and new tail rotor blades.

For a Category A takeoff on a ISA+15 day, the engines add about 600 pounds of performance lift, while the new main rotor blades add another 500 pounds, meaning one can take off the S-76D with a gross weight that is 1,100 pounds higher than what the C++ could lift. Sikorsky cites an improvement in cruise speed when considering fuel consumption; using this measure, the D model shows about 152 knots compared to the C++ with 134 knots. “This aircraft wants to get up and fly because of its power and the blades,” Altieri said.

The tailrotor blades have a one-inch longer chord, a higher life airfoil and a tapered blade tip, which allows the tailrotor to rotate slower with the same effectiveness. This slower rotation uses less power and this and the shape of the blades lowers noise by about two to three decibels. The addition of active vibration control provides more comfort for passengers and crew.

Sikorsky chose Thales TopDeck for the S76-D’s all-glass cockpit, while Rockwell Collins provides Pro Line navcom radios and Honeywell the enhanced ground-proximity warning system. TopDeck had two cursor control devices (CCDs)–one for each pilot–that use track balls to move a cursor across the two 8-by-6-inch screens in front of each pilot. The CCDs are fixed on the center console, within easy reach.

With less real estate needed for instrumentation, Sikorsky was able to shave an inch from the bottom of the instrument panel, and trimmed the glare shield a bit as well. The combined effect increases the field of view for the pilots.

Sikorsky has some 60 orders for the S-76D and has delivered about two dozen to date.

Demo Flight

Altieri obviously has much experience flying with pilots of various experience and skill, because he allowed me to lift the S-76D (N7621Y) into a hover, do a 180-deg pedal turn, take off toward the south and head along Interstate 4 at about 1,200 feet. He had me set torque at about 60 to 65 percent and then check airspeed (144 knots) and fuel burn (645 pph). The ride was very smooth, with only a slight roughness noticeable.

With five people in the cabin, a straight out-and-back trip along I-4 and oncoming darkness, aggressive in-flight maneuvering, extensive hovering and practice instrument approaches were out of the question. Altieri had me do a 180 after about 10 minutes going south and then we headed back to the Orange County Convention Center. I did the descent and landing to a hover and then lowered the N7621Y to the ground.

As we waited for the engines to cool at idle, Altieri demonstrated several more functions of TopDeck: setting up fight plans and approaches and other such functions. With no previous familiarity with the system, my head was spinning. “TopDeck has so many functions that once a pilot learns how to fly the S-76D he probably doesn’t know more than 50 percent of what TopDeck can do,” Altieri said. This I easily understood.

While the flight was short, my immediate feeling was one of envy of the professional pilots who will get to fly this helicopter all the time doing whatever they are hired to do: corporate, offshore, search-and-rescue, law enforcement and so on. For myself, I’d just like a chance to fly the S-76D again and really get to know it a lot better.

Altieri’s unabashed enthusiasm for the D model is infectious.