A man claiming to have a bomb and saying he wanted to go to Afghanistan was shot and killed yesterday after he hijacked a Northwest Orient jetliner carrying 41 people from Seattle to Portland, authorities said.

"The passengers and crew are safe," said Brent Baskfield, an airline official.

Officials identified the hijacker as Glen K. Tripp, 20, of Arlington, Wash. They said he was convicted of attempting to hijack a plane at the Seattle-Tacoma airport in 1980 and was on 20 years' probation.

FBI agents stormed the Boeing 727-200 about 2 1/2 hours after the plane landed, shooting the hijacker once with a .38-cal. revolver as passengers slid down an emergency exit chute, said FBI agent William Baker.

"It was a planned assault," said airport police chief Donald R. Jones.

A shoebox that the man said held a bomb did not contain any explosives, Jones said.

The crew of Flight 608 had separated the man from the passengers, talking to him in the otherwise empty first-class section, police said.

Negotiators had talked the man into releasing about half the 35 passengers and, as they left the craft, law officers who had crept aboard through a cockpit window confronted the man.

Passenger John Boyle of Falls City, Wash., said the man talked belligerently, saying the United States had failed to do anything to help the Afghans against the Soviet Union.