A former Navy enlisted man tried to sell submarine warfare secrets to the Soviets because he had been discharged for indecent exposure, according to authorities who said no damaging information was passed along. Craig D. Kunkle, 39, was arrested Tuesday at a Williamsburg, Va., motel as he tried to turn over classified documents to two undercover FBI agents posing as Soviet officials, said Irvin B. Wells III, head of the FBI's Norfolk, Va., office. Kunkle, a former chief petty officer, was charged with attempting to deliver classified information to a foreign government. If convicted, he could be sentenced to life in prison. An FBI affidavit filed in U.S. District Court said Kunkle was a specialist who installed submarine monitoring equipment on Navy aircraft. He served in the North Atlantic, Indian and western Pacific oceans and gained security clearance in 1984.