Air Force ‘Snubs’ F-22 Engine Cracks
The fighter aircraft is prone to cracks that develop in the J-seal, a metallic material on an inlet case that mates the engine to the airframe. The problem has led to additional inspections and costly repairs.
The Air Force Research Laboratory has designed and patented a “snubber” to act as a vibration damper and prevent cracks from developing in the engines. The product is made from a specialized silicone rubber. The same kind of damping materials are used in sporting equipment such as tennis rackets, golf clubs and baseball bats.
When cracks were discovered on an F-22 before the snubber, the engine was removed so workers could drill the crack to keep it from growing. If something went wrong during this process, the $362,000 inlet case would have to be replaced.
Each snubber is a little bigger than a quarter and costs just $35. It takes seven of them to cover the problem areas on each engine. The Air Force intends to install them on both engines of all F-22s, officials said.