Undated (AP) _ The British Airtours Boeing 737 that caught fire Thursday after its engine exploded on takeoff from Manchester, England, had been delivered new from the Seattle, Wash.-based manufacturer in April 1981, the airline said.

The airline, a subsidiary of British Airways, identified the plane as an Advanced 737-200, originally designed to seat 115 people but which can be modified to hold more.

Officials said 131 passengers and six crew members were aboard when an engine exploded. Fifty-four people died when flames swept through the cabin, officials said.

Boeing Co. spokesman Tom Cole said in Seattle that a Boeing investigation team was in contact with Boeing's technical representative in Britain, and said the team would probably go to the disaster site in line with company procedure.

The 737 was designed in 1964, and the first model flew in April 1967. The 737-200 is the standard, short-range version, while the Advanced 737-200 is modified for longer range.

The 737 has two turbofan engines in underwing pods; the plane that crashed was equipped with Pratt and Whitney engines.

David Long, a spokesman for Pratt and Whitney, confirmed that two other 737s had had engines explode in the last 18 months, one in Qatar in the Middle East and the other in Calgary, Canada. There were no deaths in those two incidents.

''But there is no reason for us to relate these'' to the Manchester crash, said Long. ''We do have our team over there and nothing they've indicates so far would draw that conclusion.''

The U.S. Air Force used the plane in modified form as the T-43A navigation trainer, according to Jane's All the World's Aircraft, a standard reference work on planes.

Fuel cells and tanks located in the wings hold up to 5,160 gallons, while an auxiliary tank in the rear lower cargo compartment of the plane's long- range versions increases capacity to 5,970 gallons.

When cruising at 33,000 feet with 130 passengers, the 737 has a range of 2,648 miles, Jane's says.