Navy Cmdr. Donal M. Billig, the former chief of heart surgery at Bethesda Naval Hospital who is charged with involuntary manslaughter in five deaths there, took the stand yesterday for the first time in his six-week-old court-martial and said he alerted a Navy recruiter about his poor eyesight and about problems he had had on a previous job.

Witnesses for the Navy prosecution have testified that Billig did not notify Bethesda about the sight in his right eye, measured at 20/400, the equivalent of being legally blind, before the Navy's flagship hospital hired him. Billig's eyesight should have kept him out of the operating room, Navy physicians testified.

Billig said he told his Navy recruiter that he had failed an Air Force physical because of his eyesight. He said he did not note it on an application form because the injury that damaged his eyesight in 1978 had not hindered his ability to perform surgery.

"If I felt that my vision was interfering with my ability to get patients in and out of the operating room alive . . . I would have stopped operating," he said.

The Navy has produced more than 40 witnesses to build its case that Billig operated at Bethesda without proper authority, and that he was "culpably negligent" in causing the deaths of the five heart patients.

The case, the second court-martial of a physician in Navy history, highlights a year of adverse reports on the state of medical service in the armed services and follows numerous audits depicting military medical facilities as plagued by quality control problems.

Billig testified yesterday he believed he had been granted full privileges to perform surgery at Bethesda, contradicting previous prosecution testimony that he had been warned he was not competent to perform surgery without supervision.

"Do you honestly believe you were authorized to operate on every one" of his surgery patients, asked defense attorney Lt. Cmdr. Stephen C. Baker.

"Absolutely," answered Billig.

The prosecution contended yesterday that Billig was asked to leave the New England Medical Center in Boston in 1972, prior to two other jobs that he also had to leave. Billig acknowledged that he was asked to leave the New England center but attributed it to the arrival of a new chief surgeon who "wanted his own team."

In 1981, Billig's privileges to practice at Monmouth Medical Center in New Jersey were revoked when a panel there found that he lacked good judgment, proper motivation and honesty. Billig testified yesterday that his problems there stemmed from jealousy and competition on the part of other doctors.

The prosecution contends Billig initially did not tell Bethesda officials about his problems at Monmouth. Billig said he told his recruiter in Pittsburgh about Monmouth, but that the recruiter, Lt. Cmdr. Jerry D. Penn, told him the problems "no longer needed to be part of my Navy record."

Billig later was fired from a group practice in Pittsburgh; he said yesterday the firing came in a disagreement over medical techniques.

Billig, also charged with 24 counts of dereliction of duty for performing surgery without proper supervision at Bethesda, began testifying yesterday in a weak and faltering voice and admitted that he was nervous. But he gained confidence as the proceedings continued and answered questions firmly and in detail.

More than once when Baker tried to interrupt his client, Billig said, "Let me finish." And three times yesterday Billig stood at an easel before the jury of nine, drawing charts and rough depictions of the heart with the assurance of a college professor giving a surgery lesson.

Reporters and military observers crowded the small courtroom, where Billig's wife Bonnie and his mother-in-law sat in the front row.

Billig said the mortality rates among his heart surgery patients did not differ significantly from acceptable rates. He said that of 95 patients on whom he performed open heart surgery, seven, or 7.3 percent, died, compared with what he said is an acceptable rate of 6 percent. Moreover, he said, 21 percent of his patients were in high-risk categories.

The Navy's probe of his qualifications began, he testified, after his former wife Marilyn threatened to tell Bethesda officials of the Monmouth incident unless he gave her $5,000.

"At that time, I was no longer paying alimony," Billig said. "I didn't owe her anything."