The Joint Strike Fighter Program will fly with stainless-steel reservoirs for its electrohydrostatic actuation system. According to reservoir supplier Senior Aerospace Metal Bellows, Sharon, Mass. (www.metalbellows.com), the reservoirs' all-welded stainless-steel construction eliminates problems typically associated with elastomeric seals on traditional piston or bladder devices.

The F-35 JSF will be designed in three variants: one for the Air Force; a short takeoff and vertical landing version for the Marines and U.K., and a carrier version for the Navy. There are 10 reservoirs for flaperons, rudder, and horizontal tails. The carrier version has two more for the ailerons. Moog and Parker Hannifin supply the overall actuation system.

A developmental F-35 is scheduled to make its first flight in 2005, with production of an operational version beginning in 2006.