Gear Box Case Coatings
I believe that Sikorsky uses either Rockhard or Sermatech coatings on all main and tail gear box housings. This was incorporated during S-92 development to improve the durability of the housings. The initial concept behind the development of the S-92 was for all of the major dynamic components to be capable of being retro-fitted on future Blackhawk/Seahawk models. As such the basic layout (i.e. foot print) would match that of the Hawk line. This design constraint may in part be responsible for some of the on going problems. The Blackhawk’s design gross weight was 18600 lbs. and its maximum all up weight of was approximately 24000 lbs. 28000 lbs may be a stretch for the present configuration.