Six air traffic controllers provided accounts of their communications with hijacked planes on Sept. 11, 2001, on a tape recording that was later destroyed by a Federal Aviation Administration manager, according to a government investigative report issued yesterday.

It is unclear what was on the tape, but its destruction did little to dispel the appearance that government officials withheld evidence, the report by the Department of Transportation inspector general said.

The report found that an FAA manager tape-recorded an hour-long interview with the controllers just hours after the hijacked aircraft crashed into the World Trade Center towers, the Pentagon and a field in Pennsylvania. His intention was to provide the information quickly to the FBI. But months after the recording, the tape was never turned over to the FBI and another FAA manager decided on his own to destroy the tape, crushing it with his hand, cutting it into small pieces and depositing the pieces into several trash cans, the report said.

The existence of the tape and its destruction were revealed in a report that initially was to find whether the FAA had fully cooperated with an independent panel investigating the terrorist attacks after the panel complained last fall that it needed more information from the agency. Inspector General Kenneth M. Mead found that the FAA never intentionally withheld information, but he condemned the managers' actions and said they were required to keep such evidence for five years.

The report said investigators were told that the tape was never listened to, copied or transcribed.

"The destruction of evidence in the Government's possession, in this case an audiotape -- particularly during times of national crisis -- has the effect of fostering an appearance that information is being withheld from the public," the report says. "We do not ascribe motivations to the managers in this case of attempting to cover-up, and we have no indication there was anything on the tape that would lead anyone to conclude that they had something to hide or that the controllers did not properly carry out their duties on September 11. The actions of these managers . . . nonetheless, do little to dispel such appearances."

The FAA yesterday said it had taken disciplinary action against the employee who destroyed the tape. That manager, identified by a source familiar with the investigation as Kevin Delaney, was last week given a 20-day suspension without pay. Delaney appealed that decision, the source said, confirming a report last night by Newsday. The employee who recorded the tape, Mike McCormick, was not subject to a disciplinary procedure and is in Iraq for the FAA, helping to set up an air traffic control system, the source added.

The FAA said it has provided thousands of documents to government investigators and the National Commission on Terrorist Attacks Upon the United States, known as the 9/11 commission.

"We believe the audiotape in question appears to be consistent with written statements and other materials provided to FBI investigators and would not have added in any significant way to the information contained in what has already been provided to investigators and members of the 9/11 commission," said FAA spokesman Greg Martin.

The 9/11 commission does not allege that FAA employees were attempting to cover up information related to the terrorist attacks. A spokesman for the commission yesterday said that it has received all information it sought from the FAA and that it interviewed controllers involved with the tape.

Evidence in the report and from the air traffic controllers union suggests that the decisions to make the recording and later to destroy it were meant to conform to traditional protocols following a plane crash. The actions also were aimed at protecting controllers who were under excessive stress and emotion, according to union officials representing the controllers.

According to the report, an FAA manager at the New York Air Route Traffic Control Center in Ronkonkoma recorded 10-minute interviews with six controllers who communicated with or tracked two of the hijacked planes.

According to union officials representing air traffic controllers, it is almost unheard of to tape-record an air traffic controller's account of an accident. The normal procedure is for controllers to provide written statements after reviewing radar and other data. A union official representing the New York controllers agreed to the tape recording on Sept. 11 because the union wanted to help law enforcement officials, but only on the condition that the tape was to be a "temporary" document, a union official said.

Ruth E. Marlin, executive vice president of the National Air Traffic Controllers Association, said she could not speak to the question of why the union official involved in the incident wanted the tape to be "temporary." "If it were me, my concern would be that if tapes were saved permanently, they might be subject to FOIA [Freedom of Information Act] request and then controllers would be subject to hearing their own voices recounted on television over and over again," Marlin said, adding that any accident can feel personal and emotional for controllers.

According to the report, a second manager at the New York center promised a union official representing the controllers that he would "get rid of" the tape after controllers used it to provide written statements to federal officials about the events of the day. The second manager said he destroyed the tape between December 2001 and January 2002.

The tape's existence was never made known to federal officials investigating the attack or FAA officials in Washington. Staff members of the 9/11 panel found out about the tape during interviews with some controllers who participated in the recording.

Staff writer Dan Eggen contributed to this report.

FAA Inspector General Kenneth M. Mead issued the report.