Raisback and Hartzell work together on new propeller design


Raisback and Hartzell work in secret to design and certify a new swept turbofan propeller family for Beechcraft King Airs.

Raisbeck Hartzell propOver the past three years, Raisbeck Engineering and Hartzell Propeller have teamed up to develop and certify the first business aviation turbine propeller using practical swept-wing theory as an integral part of its design.

The effort has culminated in the FAA certification of the Raisbeck/Hartzell Swept Turbofan Propeller for the King Air 200/B200/B200GT. The swept-back design required a new Hartzell-supplied forging before production could begin. Hartzell is currently in the manufacturing cycle. For development and FAA certification flight testing, blades machined from large aluminum blocks were used. Deliveries commence March 1st, 2013 from Hartzell’s factory near Dayton, Ohio to Raisbeck’s customers of record.

“Sexy, I’d say,” commented James Raisbeck, CEO of Raisbeck Engineering. “The overall performance improvements relative to both the OEM 3-blade and 4-blade Hartzell propellers are large, and result in greatly improved FAA-certified takeoff, climb, and landing capabilities. Their enhancement over our current Raisbeck/Hartzell Turbofan Power Props is also measurable,” he added.

Hartzell Propeller president Joe Brown applauded Hartzell’s long-term relationship with Raisbeck Engineering, going back 30 years. “Hartzell’s first development with Raisbeck resulted in the Raisbeck Quiet Turbofan Propeller System for all King Air models and is still in production. Over 2600 of these Hartzell/Raisbeck propellers have been delivered to date, making this the most successful aftermarket program in Hartzell’s history,” he commented.

The research and design phase was led by Hartzell’s Michael Schulte and Raisbeck’s Davud Kasparov. Working together between Dayton and Seattle, they created the new propeller. According to Schulte, “These new blades are a thing of beauty and offer the kind of rational expansion of our product development with Raisbeck Engineering that our companies have enjoyed together for the last 30 years.”

Davud Kasparov, Raisbeck’s resident CFD and propeller design expert, took over the program’s full responsibilities, and became its Project Engineer and Program Manager. He has successfully integrated Raisbeck’s in-house capabilities with Hartzell’s, and added outside technical consultants and DER engineers as necessary. Kasparov said the whole experience has been exhilarating. “Seeing a new concept through from the beginning sketches to the finished product and delivered to the end user is a real thrill, and an ample technical reward for me,” he commented.

The test and certification airplane was supplied by long-time Raisbeck customer Ballard Aviation of Wichita, Kansas. The flight tests were conducted by AeroAcoustics of Everett, Washington.