PIQUA, Ohio — March 25, 1998 — Hartzell Propeller announced today that the three-bladed propeller featured on Piper’s enhanced 1998 PA46-350P Malibu Mirage is a new advanced composite system and will be the first of its kind to see widespread general aviation use. The high-performance airfoils of the new propeller are constructed of Kevlar® which offers the benefits of lower weight and longer life than conventional aluminum blades. Hartzell expects to deliver over 50 composite propeller systems to the New Piper Aircraft by the end of this year.
First Deliveries Follow Accelerated Design, Development, Tooling, Testing and Certifying Process.
Hartzell was awarded the contract for the new prop in March of 1997 on the strength of its design proposal. After an accelerated, 8 month process that included complete design, development, production tooling, manufacturing, testing and certification … Piper took delivery of the first production units in November. Piper’s objective was to fit a three-bladed system to the Mirage to improve acceleration, shorten take-off rolls and reduce cabin and flyover noise levels, without paying a weight or CG penalty. Hartzell’s new propeller system directly addresses these issues.
Improved Low-Speed Thrust Delivers Real Benefits.
The new 80 inch, non-feathering, constant-speed, composite, three-bladed design offers Mirage pilots the superior low-speed thrust of an additional blade with only a minimal gain in weight over a two-bladed aluminum prop. In fact, the new composite three-bladed Hartzell weighs only 7 lbs. more than the two-bladed aluminum system installed on the 1997 Mirage. The prop also features a new, radically swept airfoil design. Take-off roll is reduced 20 percent while distance to clear a 50 ft. obstacle is reduced up to 10 percent.
Additional Service and Maintenance Characteristics Lower Cost of Ownership.
Beyond flight performance, there are additional benefits to a three-bladed Hartzell composite propeller system including: reduced vibration, lower inertia, enhanced durability and reliability, as well as improved maintenance factors.
In terms of vibration, the three-bladed prop is inherently smoother in operation. A two-bladed prop generates two large pulses of thrust compared to a three-blader’s greater number of smaller, smoother pulses. Three pulses also generate a higher frequency noise which is less objectionable to aircraft occupants. And the prop’s new airfoil design distributes the aerodynamic load more evenly from root to tip which also reduces noise levels.
The relative light weight of the blades also creates a lower polar moment of inertia which reduces load on the engine crankshaft and overall stress on the engine. This is of particular importance to aerobatic pilots such as Patty Wagstaff, Sean D. Tucker and Diane Hakala, who are all using Hartzell’s similar composite aerobatic propeller system.
In addition, the composite construction of the blades allows repairs to be made by adding material (rather than removing material as required with a metal blade) as the prop develops small nicks and gouges during normal operation. This coupled with the inherent strength of composites has enabled some airlines to put more than 30,000 hours on their Hartzell composite blades. In fact, this and most other Hartzell composite blades enjoy an unlimited service life designation from the FAA and have undergone literally millions of hours of service on commuter airliners.
Hartzell … a History of Innovation.
Hartzell Propeller Inc. is the world’s leading manufacturer of propeller systems, enjoying dominant market share in virtually all categories of propeller driven aviation including: complex piston, high-performance kits, aerobatic, corporate piston and turboprop, agricultural, military trainers and turboprop airliners. The 81 year-old company is also well-known for its design leadership having introduced the industry’s first full-feathering propellers for light twins, the first fully-reversing propellers for corporate turboprops, and the industry’s first composite structure blades.
Additional Aircraft with A Hartzell Composite Propeller System.
Piper Malibu Mirage
Aviat Pitts S2B/C
Challenger II (Sean D. Tucker)
Extra 300 (Patty Wagstaff)
Staudacher 300 (Diane Hakala)
Zivko Edge 540 (Kirby Chambliss)
Beech 1900C, 1900D