OSHKOSH, Wis. (AP) _ It was the ultimate in computer crashes.

When Ron Olstad went to pick up his luggage after arriving here on a Northwest Airlink flight, he noticed that his portable computer was missing.

That was shortly after folks in Oshkosh noticed a crash in Ronald Miller's backyard. When they investigated, they found a 20-inch by 20-inch, 50-pound computer.

''I noticed a branch had fallen and there were papers flying all over the back yard,'' said Adeline Heyer. ''I didn't hear anything, but after looking a little closer, I noticed the case.''

Miller returned home from a deer hunting trip and learned of the incident Friday, a day after it happened.

''There were papers scattered in the back yard and this big green thing,'' he said Saturday. The computer was in a canvas case. When he opened it, he found it was destroyed.

Robert Schoenfelder, Oshkosh manager for Northwest Airlink, said Sunday night that the computer apparently fell from a cargo pod as the aircraft made its final approach to Wittman Field.

He said he believed it was the first time a piece of luggage fell from a Northwest Airlink plane. Northwest Airlink, which is an Atlanta-based contracted carrier for Northwest Airlines, serves a part of the nation's midsection from Minnesota to Florida, he said.

''As far as I know, it never happened before,'' he said. ''Hopefully, it will never ever happened again.''

The Jet Stream 31 aircraft, capable of carrying 18 passengers, has a separate cargo pod carried at the bottom, Schoenfelder said, and that's where the problem occurred.

''The passengers were never in any jeopardy with the (cargo) door being open because the compartment is not a part of the airplane,'' he said.

The Federal Aviation Administration was notified immediately after the plane landed in Oshkosh and all of the carrier's aircraft were checked for similar problems, he said.

He said Northwest Airlink replaced Olstad's computer.