The chairman of a House committee called yesterday for an investigation of the Federal Aviation Administration's academy for air traffic controllers in Oklahoma City, saying there was evidence that FAA officials had tampered with test scores to increase the number of successful candidates.

In a letter to FAA chief J. Lynn Helms, Rep. William D. Ford (D-Mich.), chairman of the House Post Office and Civil Service Committee, said his staff had received information that the number of students who passed a Nov. 19 examination had risen from 79 to 95 due to manipulation of the scores.

FAA spokesman Dennis Feldman said the agency was aware of the allegations and on Tuesday a special team of academy instructors who were not involved in the test had begun to review it.

"We understand the House committee's interest and we welcome their participation," Feldman said.

Ford said he had no proof of the allegation. But a committee staff member said the charges came from people in the academy whom the committee believes to be reliable.

Over the next two years, the academy hopes to train 8,000 new controllers to replace 12,000 who went on strike Aug. 3 and were fired. In the meantime, skeleton crews staffing the control centers are keeping air traffic at about 75 percent of prestrike levels, according to the FAA.

Despite the urgency of the situation, the FAA has said, the new trainees would be held to the same standards as the old ones. Initial training runs 17 or 20 weeks, with full qualification for some jobs taking up to four years of on-the-job training.

Of 72 people in the academy's first post-strike class, 24 passed a final exam in late October, with 12 having dropped out before the test, according to academy spokesman Mark Weaver. That is a pass rate of 33 percent of the original class.

The rate for the second class was better, Weaver said. Of 143 people originally enrolled, he said, approximately 90 to 95 passed the examination that now is under investigation. Seventeen had dropped out earlier. The precise number of successful students was not available because test scores were being examined by the FAA investigators, Weaver said.

Ford asked for an investigation by the inspector general at the Department of Transportation and informed the FAA that two members of his staff would go to the academy to investigate, as well.

"We cannot afford the slightest suspicion that the lives and safety of U.S. airline passengers are being endangered for the sake of hurriedly filling depleted ranks of air traffic controllers," Ford said in a statement.