A congressional research agency, citing the increasing rate of aviation accidents involving pilot error, says the federal government should encourage airlines to tighten their screening of people flying the nation's crowded airways.

The General Accounting Office report released this week stopped short of calling for new regulations, but says the Federal Aviation Administration should encourage commercial air carriers to use the government's computer files to verify records of pilot safety.The report by the GAO, a bipartisan research arm of Congress, said airlines, spurred by deregulation, hired some 9,700 new pilots a year over the last four years.

The National Transportation Safety Board, meanwhile, cited pilot error as a factor in 95 percent of all commuter plane accidents and 63 percent of major airline accidents in 1985.

Between 1980 and 1984, by contrast, 57 percent of commuter accidents and 42 percent of major airline accidents had pilot error as a factor, GAO said.

"The high percentage of accidents and incidents in which pilot error was a factor, and accidents involving pilots with a history of safety transgressions, indicate that airlines should use available resources to help assure that the pilots they hire fly as safely as possible," the report said.

The NTSB earlier this year pinned the blame on an Aug. 16 1987 crash of a Northwest Airlines flight at Detroit's airport on the failure of the two pilots to follow required checklist procedures for takeoff. The crash killed 156 people on board and a four-year-old girl survived.

The Air Line Pilots Association attacked the report when it was released in May, saying the safety board didn't give enough weight to mechanical failure of cockpit instruments.

In its report, GAO said the federal requirement for security checks involves only verifying pilots' employment history for the prior five years.

"Airlines are responsible for developing their own hiring criteria in line with corporate preferences," GAO said.

It said 62 percent of the airlines surveyed did nothing to verify pilots' certificates and 56 percent did not check with the FAA to check on past safety violations fliers may have.

The research agency said, for instance, that pilots of a commuter plane that crashed in Durango, Colo., in January had received warning letters from the FAA but the airline was not aware of the citations.

Airlines should be encouraged to use the FAA's own computerized listings, including the Accident Incident Data System and the Enforcement Information System, to verify what the pilots provide and to give a broader background of the pilots, GAO concluded.