A tape made hours after the Sept. 11 attacks that recorded statements of air-traffic controllers on Long Island was destroyed and never given to authorities, a federal investigation reported Thursday.

The hour-long tape of six controllers who tracked the planes flying toward the World Trade Center was cut into small pieces a few months later by a manager at the New York Air Route Traffic Control Center in Ronkonkoma.

The manager, identified by officials as Kevin Delaney, told investigators that making the tape contradicted Federal Aviation Administration policy and that the recordings were "of minimal value" because controllers also gave written statements about the hijackings.

Delaney added that because controllers were stressed on Sept. 11, 2001, they "were not in the correct frame of mind to have properly consented to the taping," said a report by Transportation Department Inspector General Kenneth Mead.

Delaney faces a 20-day unpaid suspension and filed an administrative appeal, an official familiar with the probe said.

The FAA is looking into disciplining center manager Mike McCormick, who withheld the tape from superiors after agreeing to the controllers' union condition that the tape be destroyed once written statements were recorded. McCormick is now working for the FAA in Iraq helping establish an air-traffic-control center.

The tape's value is unclear because no one ever listened to it, transcribed it or duplicated it, the investigation found.

Its existence was not known outside the Ronkonkoma center until October, when the independent commission investigating Sept. 11 was gathering records from the FAA and found an evidence log that mentioned the tape. The center monitors high-altitude planes in the metropolitan area.

FAA spokesman Greg Martin said the tape "would not have added in any significant way to the information already provided." The FAA has given the commission 150,000 pages of documents, 230 hours of tapes from Sept. 11, radar trackings of the planes and digital recordings, Martin said.

Kristen Breitweiser of New Jersey, whose husband, Ronald, was killed in the trade center and who closely monitors the commission, was "furious."

"That's destruction of crucial evidence, and the person [who destroyed it] should be held criminally liable," she said.

Mead said he gave information to the office of Roslynn Mauskopf, U.S. attorney for the Eastern District of New York, who declined to bring charges due to "lack of criminal intent and prosecutive merit."

Sen. John McCain (R-Ariz.), who had requested Mead's investigation, called the destruction of the tape "disturbing" and said he may hold a hearing.

The commission said it would consider Mead's investigation in its report.

McCormick made the tape starting at 11:40 a.m. on Sept. 11 by having controllers gather in a windowless room and speak into a microphone for five to 10 minutes each. McCormick told investigators he feared controllers would take sick leave, and he wanted a record of their accounts "to be immediately available for law enforcement."

When McCormick sought approval from Mark DiPalmo, head of the controllers union in Ronkonkoma, DiPalmo expressed concern because tape recordings are not typically made of controllers after an aviation incident, though they are not prohibited.

McCormick assured DiPalmo that the tape would be given only to law enforcement and would be "a temporary measure until written statements could be prepared," according to the investigation.

Asked Thursday if the tape was to be destroyed, DiPalmo said, "I don't think I'm prepared to comment on that. The tape was not in my custody."

McCormick withheld the tape from the "formal accident package" the center gave the FAA in November 2001.

Delaney, who was the center's acting quality-assurance manager, told investigators he destroyed the tape between December 2001 and February 2002, because "he felt strongly that the tape never should have been made." He is now a center operations manager.

The probe said the tape was an original record and should have been kept for five years under FAA policy. Destroying evidence, it added, "has the effect of fostering an appearance that information is being withheld from the public."

The probe also found that the FAA didn't intentionally withhold documents from the 9/11 commission.

Staff writers Sylvia Adcock and Anne Q. Hoy contributed to this story.