Boeing Develops Blade Fold Kit For WAH-64 Apache Longbow, Envisions Use By Defense Forces Worldwide
A unique blade fold kit, developed by The Boeing Company for use on the WAH-64 Apache Longbow, has the potential to become the standard for the entire Apache fleet worldwide.
The blade fold kit was unveiled Sept. 28 in Mesa, Ariz., at the rollout of the first WAH-64 Apache Longbow for the United Kingdom.
Boeing delivered the aircraft to prime contractor GKN Westland, which plans to deliver its first WAH-64 to the U.K.'s Ministry of Defence in early 2000, the same time the kit will enter service with the British Army.
More than 900 AH-64A Apaches in service around the world are candidates for the blade fold kit, which would give operators the ability to store their aircraft in confined spaces, including aboard ships. The kit works equally well on both AH-64A and AH-64D aircraft, which share identical rotor hubs, blades and tail booms.
The kit also is designed to prevent damage to the blades when storing the aircraft on flight ramps or to help camouflage the aircraft when used in battlefield conditions.
The blade fold kit allows maintenance personnel to manually fold the Apache Longbow's blades in winds up to 45 knots and effectively protects the blades in the stowed position at winds of up to 70 knots. A unique design feature of the kit allows maintainers to lock the blades into set positions that reduce the stress loads that could be applied by high winds.
The blade fold kit uses a series of easy-release locking assemblies to secure the blades, a saddle assembly to anchor the blades to the tail boom, four positioning links and four anchoring poles to keep the blades at the proper angle, and a walkaround pole to guide the blades into their stowed position.
In designing the kit, Boeing changed only four bolts and added four washers to the aircraft. The kit requires no special equipment, using quick release pins and over-center cams to secure the blades, and the only tool needed is a half-inch ratchet with a 3/4-inch socket.
Boeing developed the blade fold kit to meet requirements set by the British Ministry of Defence, which plans to use the WAH-64s for a variety of applications, including shipboard operations.
The design has proven so successful that other Apache operators are studying the feasibility using the blade fold kit for their own aircraft.
Boeing built the prototype in Mesa to validate the effectiveness of the kit before going from design to production.