A Look At The F-35 Joint Strike Fighter

The F-35's specification called for sustainability in service and, in an uncharacteristic move for a top-tier warplane, affordability.


Lessons learned

Other pieces of the aircraft demonstrate that lessons have indeed been learned. David Lawrence, who worked on the F-119 engine core, remembers a mechanic’s comment that, when a particular component was removed when the engine was in a certain orientation (and it’s not always possible to optimally orient an engine in the field!), another part would invariably drop into the works. The result of that mechanic’s comment was to design a small relief into the housing, through which a tool could be inserted, to hold the part in place long enough to support it formally.

Joel Malone, a retired Air Force colonel, now working in business development for Lockheed Martin, worked with other teams to simplify support. The F-16, he notes, has an APU that needs Hydrazine; the F-35 uses jet fuel, which comes from the same tanks as the engine’s supply. As a bonus, there is no LOX (liquid oxygen) requirement on the F-35.

The F-35 canopy opens from the front, presenting lower visibility surfaces for the bad guys to find and also requiring smaller actuators. It re-aligns on closing … and the pilot can see it. As is current practice, the F-35 pilot is ejected through the canopy. As crude as it is, it’s … simple.

Added concerns were made to provide access panels; there is a panel near the fuel port on the starboard nacelle that allows a laptop hookup for full-system diagnostics on the ground — using COTS electronics. Speaking of the fuel port, there is only one; when the Lightning II is full, it’s full.

Commonality is king

Across the F-35 platforms, too, commonality is king. The cockpits, weapons, avionics — all are identical, and all are as simple and available as the mission could allow. Hydraulics are backed up by a “quad-redundant” fly-by-wire system, saving weight and complexity. For example, the F-35 can fly with one horizontal tail and one rudder missing.

Some 97 percent of the F-35’s electronics are “first-tier accessible” i.e., accessible without taking other things apart; and unlike the F-15 and F-16, which have LRUs (line-replaceable units) running everything that’s connected to a wire, the F-35 saves time, money, and logistics nightmares by employing LRCs — line-replaceable cards. Only two systems on the F-35 need full LRUs.

How much of this technology will trickle into civilian aircraft — or has migrated from civilian practice to the military — is a huge topic, hampered for the moment by necessary military secrecy; but the trends across aviation — toward access; field identification, maintenance, and repair; component availability; and cost containment — are obvious, and are improving, as each new design emanates from the engineers’ computers.

 

For more information: www.f35.com; and http://www.rolls-royce.com/defence/products/combat_jets/rr_liftsystem.jsp.

We Recommend