Electromechanical Actuators (EMAs) for wheel brakes for business aircraft at 20,000-pound MTOW or less, and helicopters at 40,000-pound MTOW or less.
Aircraft electric brakes have been successfully introduced to larger airliner type aircraft such as the B787, which improves system safety. The business aviation sector will realize similar improvements to safety, price, performance, and reliability by implementing electric braking. However, the small wheel and tire size used on this family of aircraft limits the available envelope to mount electric brake devices. A novel EMA design that produces a very high-power density, small package size, meets performance, is price competitive to existing fluid power, and exhibits high reliability while operating in an extremely difficult environment had to be created.
The stopping requirements for the aircraft were translated down to applicable brake loads at each main landing gear on the aircraft. Each landing gear brake load was then divided between the number of wheels mounted to it. The required force for each EMA was then determined from the needed brake forces at each wheel. Aircraft safety, brake force, space claim, and subsystem redundancy determine if 1, 2, or 3 EMAs are required at each wheel. Ingenium Aerospace’s hi-resolution, 3-D CAD models and renderings of the landing gear and wheel structure, along with analytical consideration of the deflections in structural elements (tires, link arms), defined the EMA envelope and number of EMAs per wheel. The selected EMA configuration incorporates a frameless, BLDC motor driving thru a miniature geartrain to engage a worm gear set.
Results & Outcome
Trade-off studies were completed to assess the benefits and drawbacks of EMA configurations exhibiting optimal performance versus more cost-effective solutions. Numerous configurations were evaluated. The configuration identified above was the basis for prototype development and laboratory tests. At the completion of prototype testing, Ingenium Aerospace designers will commence a secondary design effort to repackage the EMA elements into a smaller integrated package within the Brake Torque Plate.