Aug 13 (Reuters) - U.S. President Donald Trump has ordered

the Navy to abandon a complex system for launching jet fighters

from its aircraft carriers and instead go back to using steam

catapults, the White House said on Thursday.

Trump signed a national security memorandum directing the change

which would require the removal of the electromagnetic catapult

system used on Gerald R. Ford-class aircraft carriers and is

expected to cost billions of dollars. Huntington Ingalls

is the primary contractor building Ford class aircraft

carriers.

Trump has frequently criticized the Navy's electromagnetic

launch system as being more expensive and not as effective as

steam catapults.

"Billions of dollars more they spent on electric catapults

and they're not good. They're not nearly as good, too complex,"

Trump said at a defense summit in Pennsylvania last month.