The Army, in an attempt to prevent cancellation of its entire $66 billion LHX helicopter program during the Pentagon's budget-cutting review, has recommended that the project be cut to $30 billion through 2010, Army leaders said yesterday.

They said the idea was approved by Robert Costello, the Defense Department's undersecretary for acquisition, but still must pass muster in separate reviews by Defense Secretary Frank C. Carlucci and his deputy, William H. Taft IV. The original LHX program, calling for more than 4,000 helicopters at a cost of $66 billion, would have been the biggest procurement in Army history.

Lt. Gen. Donald S. Pihl, a top executive in the Army's aviation program, said the stripped-down LHX program would build only the light attack version of the helicopter to replace Vietnam-era helicopters. The original idea was to build a big attack version of the LHX and a transport chopper as well.

Under the Army's plan, the Apache attack and Blackhawk transport helicopters would remain in production to fill the gaps left by the scaling down of the LHX program.

Pihl said that the Army could reduce its LHX request for fiscal 1989 from the planned $500 million to $250 million or less by settling for just one version of the LHX. He added that the Army still hopes to get the other versions of the LHX when budget constraints are not as severe.

"We've refocused the program," the general said, adding that the controversial LHX project has not been canceled outright as many have been predicting during the current budget crunch. However, cancellation is still a possibility, Army officials conceded, if Carlucci and Taft reject this latest rescue effort.

Four aerospace contractors have the biggest stake in the future of the LHX. The team of McDonnell Douglas Helicopter Co. and Bell Helicopter Textron Inc. is pitted against the team of the Boeing Co.'s Vertol division and United Technologies Corp.'s Sikorsky Aircraft division.