Helicopter Composite Rotor Blade Development
ATI has developed many full-scale experimental rotor blades. Previous designs have included tip-jet propulsion devices, piezoelectric and mechanically actuated trailing edge flaps, shape-memory alloy twist-actuators, and active/passive flow-control mechanisms. Blade geometries have included non-linear and high-twist distributions, anhedral/dihedral tips, swept tips (both forward and aft), and variable chord/thickness distributions to name a few. We have developed full-scale blades less than 12 inches long (on UAV applications) to over 30 feet.
Many of our designs involve full instrumentation including strain-gages, static/dynamic pressure transducers, accelerometers, thermal sensors, hall-effect sensors, and more. From initial concept, preliminary design, analysis, fabrication, instrumentation, calibration and testing, ATI can supply the engineering and fabrication resources needed to ensure a successful blade development test-program.
S-61 Main Rotor & Tail Rotor Blade Development
ATI designed, analyzed, and tested composite main-rotor blades to replace the metal blades on Carson Helicopter's S-61 (H-3). ATI fabricated the first flight-certified sets of the rotor-blades as well as the static and fatigue test articles. ATI also developed the S-61 composite tail rotor blades which have been successfully flight tested.
Flight testing showed the composite main-rotor blades provide up to a 2,000 lb. increase in gross-lift capability, an additional 15 knots in airspeed, or an increase in range by over 60 nautical miles. The blades are in production and have been in-service for over 10 years. The current certified FAA life-limit of these blades is 10,000 hours and may be further expanded in the future.
Sikorsky's latest modernized version of the S-61, the S-61T, is fitted with the ATI composite blade design and is currently seeing service in world-wide military and civilian applications.
The composite tail-rotor design was completed in February 2012 with the ATI-fabricated first FAA conformed blade set. Flight-testing demonstrated that the composite tail-rotor blades had no design anomalies and had significantly lower vibration levels than their aluminum predecessors. Manufacturing and production is currently being undertaken by Carson Helicopters in their new blade manufacturing facility in Fort Monroe, VA.
Bell 429 & Erickson S-64 Composite Helicopter Blades
ATI worked with Bell Helicopter to develop and fabricate the Bell 429 rotor blades. We developed the manufacturing process, the detailed process documentation, and fabricated the first 3 sets of flight blades and fatigue test articles. The first-flight was remarkable in that the blades were installed and successfully flown hover-in-ground-effect all in Day-1 of flight testing.
ATI provided the design and analysis of Erickson Air Crane’s S-64 Composite Main Rotor Blades conforming to FAA STC certifications. These rotor blades incorporate advanced airfoil technology, twist, and swept tips for improved performance and extended life. ATI fabricated the first FAA conformed blades and fatigue-test articles while Erickson Incorporated is currently working to manufacture the production blades at their facilities. Erickson expects certification of the production blades in 2015.
ATI's State-Of-The-Art Facility & Equipment
In 2015, ATI added a new composites fabrication facility, over 20,000 square-foot, with 2 environmentally controlled assembly rooms (large: 10,000 sq. ft. and small: 3,000 sq. ft.) with pre- and post-processing assembly areas. Our large environmentally controlled assembly room features overhead lifting (for large tooling) up to 20 tons. A new autoclave, along with ovens, presses, ply cutting machines, and large material freezer storage units permit ATI to fabricate composite components efficiently while meeting the processing specifications of our customers.
ATI’s autoclave is capable of processing up to 26-foot and ovens cure up to 34-foot long blade tools. ATI has multiple walk-in freezers for composite material storage and 2 NC ply cutting tables with multiple layup tables suitable for blades up to 34 feet in length.
We are a FAA conformed, clean room facility and have the capability to perform endurance fatigue testing on both full scale and scaled dynamic system components.