Naval Air: F-35 Hot Stuff Cooled Down

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July 20, 2010:  The navy has found a way to handle the heat. Over the last two years, the U.S. Navy discovered that the engine exhaust heat from its two newest aircraft, the tilt-rotor MV-22 and the vertical takeoff F-35B's, was too hot for the deck plates on some of the carriers these aircraft will operate from. The gas turbine engines of both aircraft, which blow their exhaust right on to the deck of the carrier while waiting to take off, caused high enough temperatures to the steel under the deck plates, to possibly warp the understructure. The navy also discovered that the exhaust heat problem varied in intensity between different classes of helicopter carriers (each with a different deck design.)

The navy sought a solution that would not require extensive modification of current carrier decks. This includes a lot of decks, both the eleven large carriers, and the ten smaller LHAs and LHDs. This began looking like another multi-billion dollar "oops" moment, as the melting deck problem was never brought up during the long development of either aircraft. Previously, the Harrier was the only aircraft to put serious amounts of heat on the carrier deck, but not enough to do damage. But when you compare the Harrier engine with those on the V-22 and F-35B, you can easily see that there is a lot more heat coming out of the two more recent aircraft. Someone should have done the math before it became a real problem.

In any event, inexpensive solutions were found, sort of. For the MV-22, the navy developed portable heat shield mats, that deck crew could drag into place under the exhausts of the MV-22s, if these aircraft were expected to be sitting in one place for a while.

For the F-35B, the heat shield mats don't work as well (the F-35B engines put out more heat), so the exhaust nozzle on the F-35B engine is being redesigned, to spread the exhaust over a larger area, thus lowering the peak heat build up to the deck plates. This would also help solve the problem of the F-35B turning asphalt surfaces to a liquid state.

Both the MV-22 and F-35B are expected to continue creating "heat management" problems.