BERLIN (AP) _ The U.S. Air Force on Tuesday dropped negligent homicide charges against an F-15 pilot in the downing of two Army helicopters that killed 26 people in April.

But Lt. Col. Randy W. May, a decorated 19-year veteran and squadron commander, could still face disciplinary action ranging from reprimand to dismissal, said an Air Force spokesman.

May and his lead pilot, Capt. Eric A. Wickson, shot down the Black Hawks over northern Iraq on April 14, mistaking them for Iraqi Hinds in violation of a no-fly zone.

No one had told the pilots that ''friendlies'' were in their air space.

The fratricide deeply embarrassed the Pentagon, whose investigation revealed command failures at several critical levels and a dangerous pattern of lax communications between the Army and Air Force.

Only one officer charged in the case will face court martial - a captain in charge of the AWACS radar plane that failed to inform May and Wickson that two Army UH-60 helicopters were in the area.

That officer, Capt. Jim Wang, will be tried for dereliction, the Air Force announced on Monday in the United States. Dereliction charges were dropped against five other AWACS officers.

Maj. Gen. Eugene Santarelli, commander of the 17th Air Force based at Sembach, Germany, dismissed the charges against May based on an Air Force investigation.

Wickson, who was never charged, made the initial sighting of the helicopters, misidentifying them as Iraqi. May then flew over and confirmed the erroneous identification. Radio transmitters on the Black Hawks that were supposed to identify them as U.S. craft were transmitting the wrong signal.

The Air Force said May was charged because he apparently ''gave a vague response to Wickson's query about the identity of the helicopters.''

May contested that claim, and called his decision to fire the last action in a long chain of errors.

May, who was decorated for downing an Iraqi Hind helicopter during the Gulf War, remains based with a fighter squadron at Spangdahlem Air Base in Germany.

He issued a statement Tuesday saying he was relieved and apologizing to the families of the victims - 15 Americans, five Kurds employed by the United States and military officers from Britain, France and Turkey.

The Blackhawks were ferrying members of an international group that had been working with the Kurds in northern Iraq since the end of the 1991 Gulf War.