LONG BEACH, Calif. (AP) _ David A. Burke was not a vindictive murderer, despite evidence suggesting he killed a planeload of people to get even with a boss he believed was out to get him, his brothers say.

''To say that he was a distraught employee who lost his job and wanted to kill everybody, that's crazy,'' said his brother, Altamont Burke, 27, of Atlanta.

Both he and Allan Burke, 37, of Rochester, N.Y., have come to Long Beach to try to learn what happened to their brother.

Federal investigators believe Burke used a gun and possibly explosives to cause the crash of Pacific Southwest Airlines Flight 1771 on Monday. The jet smashed onto a hillside near Cayucos in central California midway through its flight from Los Angeles to San Francisco, killing all 43 on board. Burke, who had worked for USAir, parent company of PSA, for 14 years, was fired by his supervisor, Raymond Thomson, on Nov. 19.

Burke's discharge apparently climaxed a five-month feud between the men. Burke, who was black, had alleged to state authorities long before he was fired that Thomson had passed him over for promotion because of race. The two met several times after Burke was fired, including the day of the crash, but Burke was not reinstated.

FBI officials said Burke, armed with a .44-caliber Magnum and possibly explosives, boarded Flight 1771, knowing Thomson was on it. During the flight, he wrote Thomson a death note on an air sickness bag, apparently shot Thomson in the cabin, entered the cockpit and killed the pilot and perhaps the co- pilot.

''They're trying to solve a case and he's the logical one to hang it on,'' Altamont Burke said Thursday. ''How do you find a note like that on a plane that smashed into a million pieces? I don't believe any of that.''

The brothers also disputed the accounts of friends who described Burke as a woman beater and drug smuggler.

Since August, Altamont Burke said he and his brother had discussed several business opportunities, including a franchise on condom vending machines.

But the most promising venture was a check-cashing franchise in Los Angeles, and David Burke had already invested at least $4,000 in it, his brother said. The deal was supposed to have closed next Tuesday.

''He was the backbone of the family,'' Altamont Burke said. ''He was a very generous person. He always looked out for the well-being of the family.''

Although Burke had talked to several family members during the last month, he told none that he had been fired or that he had broken his engagement to Jacqueline Camacho of Hawthorne, the brothers said.

Burke had transferred to Los Angeles a year ago.

Allan Burke said his brother must have been hurt by his treatment at USAir in Los Angeles. It was the first time his brother ever failed at anything, he said.

On July 15, Burke complained to the state Department of Fair Employment and Housing that he had been passed over twice for promotion to customer service supervisor.

Burke alleged white workers with less experience were promoted to the supervisory positions and blamed Thomson for the alleged discrimination. But he decided against filing a formal complaint, said Annabella Hwa, the department's district manager in Los Angeles.

Although investigated several times for alleged drug involvement and auto theft in New York, Burke was never charged.

Burke's last will, dated Nov. 30, named six children as beneficiaries, although Burke was never married, Altamont Burke said. The Burke brothers said David Burke cared for 13 children, although he fathered only seven.

Beatrice Burke, who identified herself as his common-law wife, and Ms. Camacho filed reports with police alleging they were assaulted by Burke. In 1985, Beatrice Burke's case in Rochester was dismissed when she failed to appear in court. Ms. Camacho's case was pending when Burke died.

Real estate records in Rochester show Burke was given his first home by his Jamaican-born, taxi-cab-driver father as a high school graduation gift. Burke used the profits from its sale to buy other property and made a $200,000 profit from the sale of two homes this year.