A $35 "snubber" developed by the Air Force Research Lab’s Propulsion Directorate, is a vibration damper that will prevent cracks in the J-seal on the F-119's engine inlet case, a spoked, ring-like device that helps control the air going into the engine.
Previously, if cracks were discovered, the engine would need to be pulled, and the end of the crack drilled to stop it from growing. If any problems arose during drilling, the $362,000 inlet case had to be discarded. The little orange snubber looks like an exotic pencil eraser and fits in the gap opposite where the J-seal is welded to the inlet case. Seven $35 snubbers are fit on each engine, meaning outfitting each F-22 costs $245.
The snubbers began being used in April 2011, and about 3,000 flight hours have been logged. They were designed to last half the life of the engine, but because they're so inexpensive, new ones will be installed whenever the engine is pulled.
In the long term, the plan is to show that the old cracks don't grow once the snubbers are installed, and further stop-drilling won't be required.
