SEATTLE — The Raisbeck Swept Blade Turbofan Propellers for all King Air C90s are available for deliveries beginning in January 2014.
These propellers, which represent the continuing advance in swept-wing theory under a joint development program with partner Hartzell Propeller, follow the introduction of the Swept Blade Propellers for the King Air 200 family last January, company officials note.
All C90GTx, C90GTi, C90GT, C90B, C90A, C90 and E90 aircraft will accept these newly designed propellers. They can be installed as an upgrade to existing 4-blade propellers (replacing either Raisbeck Turbofans or Beech’s OEM propellers), alone or in combination with Raisbeck’s EPIC Performance Package.
“We call it ‘The Wave of the Future’ in propellers,”commented James Raisbeck, CEO and founder of the company. “Of all the improvements our company has made to the King Air family over the last 31 years, this one is clearly the most visible and impressive.”
The propeller diameter is increased a full six inches, from 90 to 96 inches. Blade quarter-chord sweep has been increased on this model to 30° at its outer diameter. Propeller blade sweep allows the increase in diameter while simultaneously reducing noise, according to company officials.
Overall thrust and efficiency are improved, officials add. These features also provide 1,750 rpm cruise, which lowers the cockpit and cabin sound levels even further. FAA and European certified noise levels have been reduced on the C90GTx by 1.6 dBA to 74.6 dBA.
Combined with Raisbeck Dual Aft Body Strakes, these propellers offer measurably better FAA-approved performance across the board, but particularly in takeoff, climb, approach and landing, company officials state. At Raisbeck’s maximum takeoff weight of 10,500 pounds, takeoff distance over a 50-foot obstacle is 2,150 feet flaps-up, a reduction of 850 for the C90GTx, for example. Landing distance over a 50-foot obstacle is further reduced by 360 feet to 2,120 feet at maximum landing weight, without propeller reverse. With reverse, this distance is further decreased by 1,580 feet.
Detailed propeller design on the C90′s propellers began shortly after completion of the Swept Blade Prop program for the King Air B200GT/B200/200 family, which was introduced into service in January 2013. Development and certification flight tests, conducted at Boeing Field International in Seattle, were completed in early summer. Flight manuals, installation manuals and other documentation are being completed for first customer deliveries in early January 2014, either as a standalone or in combination with Raisbeck’s EPIC Performance Package (which includes Dual Aft Body Strakes, Increased Gross Weight and all increased FAA-certified performance).