By LIZ BALMASEDA
Herald Staff Writer

The hysterical hijacker who successfully commandeered a Miamibound Capitol Air DC8 to Havana on Sunday had a familiar method and madness. He was identified Wednesday as a diagnosed paranoid schizophrenic who had failed in two previous attempts to hijack airliners to Cuba.

Arrested by U.S. officials after the other attempts, the suspect then slipped through the legal system because he was found mentally in competent to stand trial.

Henry Dargan McMaster, U.S. Attorney in Charleston, S.C., identified the hijacker as Rigoberto Gonzalez, 51, who once told FBI agents he wanted to go to Cuba to "join the revolution - "

ter recognized the behavior of Sunday's hijacker: The man claimed to have a bomb and a gun. He locked himself in the bathroom of the jet. He demanded to go to Cuba.

Twice before, McMaster said, Gonzalez had tried similar tactics. At 8:27 p.m. Sunday, he finally got to Cuba - and was taken immediately to jail.

McMaster said Gonzalez commandeered an Air Florida flight in March 1981. Aboard the jet, Gonzalez dumped a briefcase in the aisle. He said it contained a-bomb. Then he locked himself in the bath and began shouting, "Viva Cuba!" He eventually was coaxed out of the bathroom and arrested after the flight was diverted to Charleston.

Investigators opened the case. They found it filled with socks and Vienna sausages.

In June 1979, Gonzalez again allegedly  tried to hijack a plane. time he brandished a bottle of Q rum and ordered the pilot of an Eastern Airlines jumbo jet to Cuba.

"Viva Cuba!" he shouted outside the locked cockpit door. He was subdued by two flight attendants and two passengers,

In both cases, Gonzalez was found mentally incompetent to stand trial.

On Sunday, officials familiar with the case say, Gonzalez, a former  keypunch operator, boarded Capitol Air Flight 236. The San Juan-to-Miami flight carried 202 passengers and a crew of 10. One hour and 13 minutes after takeoff, Gonzalez demanded to be taken to Cuba.

McMaster said Sunday's hijacker was Gonzalez. "We learned it was in fact the same man we tried to take to trial for so many months," McMaster said. "Our office was contacted by the FBI."

FBI spokesmen in Miami and Puerto Rico would not confirm or deny the hijacker's identity.

The crew and passengers were returned the following day. The hijacker remains in Cuba.

When Gonzalez was arrested in 1981, he was sent to Springfield, Mo., for psychiatric evaluation. He was found mentally incompetent to understand the charges against him and to assist in his own defense, McMaster said.

"They, said he was suffering   from  a mental defect or disease at the, time of the incident," McMaster said.

In June 1981, U.S. District Judge Sol Blott in Charleston sent Gonzalez to a federal institution in Butner, N.C., for more tests.

"He was found mentally competent to stand trial while on medication," McMaster said. "So we indicted him on November 1981."

That same month, Judge Blott ordered him to a state facility in Columbia, S.C., for further evaluation. He was there four months, Again he was found mentally incompetent.

In February 1982, McMaster's office requested a fourth evaluation.

"The conclusion was that he was presently competent to stand trial while on medication, but he lacked capacity for criminal intent at the time of the crime." McMaster said.

Unable to prosecute him, McMaster's office placed Gonzalez in a pre-trial diversion program in Charleston. But that, too, brought problems. Gonzalez could not speak English, he could not get a job, and he could not find his family,

So on Feb. 9 "at the request of everyone involved" - Blott ordered that Gonzalez be transferred to a pre-trial diversion program in San Juan, where he had relatives and job possibilities.

"We didn't hear anything else about him..."  McMaster said.

"Until Sunday, that is."