The Cuban air force general who fled to the United States last month said widespread domestic opposition to Cuba's involvement in the Angolan civil war has prevented Fidel Castro from intervening more forcefully in Nicaragua.

President Castro knows the Cubans will not accept a massive infusion of troops in another country, Gen. Rafael del Pino Diaz said, and has therefore limited the Cuban presence in Nicaragua to 300 or 400 "advisers."

Del Pino made his statements to Radio Marti, part of the Voice of America, in nine hours of interviews edited for broadcast to Cuba. A summary of the interviews was made available yesterday.

The Cuban strategy in Nicaragua is to "weed out" members of the Sandinista leadership who oppose Cuban influence and thereby establish a "robot" regime controlled from Havana, del Pino said.

"This will provide Castro a non-Cuban contingent, still under his control, to carry out internationalist missions while disclaiming direct Cuban involvement," he said.

Del Pino denied reports attributed to him that Nicaraguan pilots are training in Cuba and that Nicaraguan MiGs are based on the island.

Government officials yesterday maintained the secrecy that has surrounded del Pino since he arrived in Florida May 28, refusing to discuss his whereabouts or his debriefing by U.S. intelligence agencies. White House spokesman Dan Howard would say only that "the information we have obtained from the general is extremely valuable."

In his interviews with Radio Marti, del Pino described deepening Cuban disillusionment with the war in Angola, which has left 10,000 Cuban soldiers killed, wounded or missing in action, he said.

The prevailing opinion within the Cuban military command is that the war is lost," del Pino said, adding, "Only Fidel and Raul Castro {Cuba's first vice president} have any faith in victory."

Del Pino, who headed the Cuban air force in Angola during 1975 and 1976 and returned frequently in later years, said Cuba remains mired in the African conflict to repay debts to the Soviet Union by helping it secure a base in the South Atlantic, to alleviate growing Cuban unemployment and to provide a place to send military officers to be punished.

Cuba's ruling elite are insulated from the human cost of their policy because their sons are exempt from military service, the general said. But if a bureaucratic foul-up should land them in Angola, "Things are fixed so they serve {away from the fighting} where the greatest danger to them is getting malaria from a mosquito bite."

Del Pino said Angola has come to be viewed as "the Cuban Vietnam" and told stories of young Cuban soldiers perishing on arbitrary missions for which they were ill-prepared. He accused the Cuban leadership of "playing with the life of youngsters" and said the government's treatment of soldiers as "cannon fodder" contributed to his disaffection.

On another subject, del Pino said Cuban soldiers are tested for the AIDS virus when they return from Africa and are imprisoned in an isolated facility south of Havana if they test positive. High-ranking officers regard this policy as "unfair and inhumane," he said.

According to Radio Marti Director Ernest F. Betancourt, who conducted the interviews, del Pino attended high school for two years in Knoxville, Tenn., and knew that he would be able to "say all he felt and unmask the reality of what is happening in Cuba" if he reached this country.