Ground control calls him "The Baron."

When his F-5 breaks the sound barrier, Capt. Jeffrey Sturmthal of the U.S. Air Force transforms himself into a Soviet fighter pilot.The 30-year-old Californian flies with the Aggressor Squadron, whose 14 pilots try to think, act and fight like the imaginary enemy.

The unit at Clark air base, 50 miles north of Manila, trains U.S. pilots on what to expect if they meet Russians or North Koreans in combat.

The Aggressors head the "Red Force" in mock air battles, using Soviet or North Korean formations and strategy, gleaned from intelligence reports. Their mission is to outwit the "Blue Force," made up of pilots from America, the Philippines, Australia, Singapore and Thailand.

Sitting in an office surrounded by model Soviet jets, Sturmthal said his job makes him part actor, part psychologist.

"Americans are more free thinking and their flying is more free style," he said, comparing pilots from the two superpowers.

He said Soviet pilots depend more on ground control. American pilots, instead, look to their flight leader.

As many as 30 planes take part in the exercises, eight in each dogfight. A pilot sighting an "enemy" in missile range pushes a button - the aircraft carry no weapons - and announces "You're dead" over the radio. The other lands.

Back at headquarters, officers study videos of each pilot's cockpit view and of ground control radar.

The Aggressors, in the Philippines since 1975, are due to transfer out this fall, but their destination has not been announced. They are expected to switch to the more modern F-16, better equipped to simulate the Soviet MIG-23 or MIG-29 fighters.

The unit at Clark, another squadron in England and two in Nevada were formed in response to the Vietnam War, where analysts said Americans were poorly trained for air combat and familiar only with U.S.-style tactics.

"When I flew in Vietnam, I knew nothing about the enemy," says Aggressor commander Lt. Col. William Finocchio.

His pilots and radar controllers become experts in Soviet aircraft, air-to-air missiles and North Korean pilot techniques during their two to three years of training.

"Simulate the threat," advises a wooden plaque on Sturmthal's office wall. The "Atoll Bar," a lounge down the hall, takes its name from the U.S. codeword for a class of Soviet air-to-air missiles.

When Finocchio's men leave the Aggressors, they retrain to fly American-style.

"They have to stop thinking bad guys and start thinking John Wayne."