Relatives of the 44 passengers and crew killed Sept. 11 aboard hijacked United Airlines Flight 93, which crashed in rural Pennsylvania, will be allowed to hear the cockpit recordings during a single, private listening session next month, the FBI says.

The highly unusual decision was approved personally by FBI Director Robert Mueller, an FBI official, speaking on condition of anonymity, confirmed Monday. Families have been asking the FBI to let them hear what transpired in the cockpit after some passengers apparently rushed the hijackers with the cry, "Let's roll!''

Attorney General John Ashcroft has praised the Flight 93 passengers as heroes ``who sacrificed themselves in a field in Pennsylvania so terrorists would not succeed in striking Washington a second time on September 11.'' He called their actions ``the most dramatic of the heroic acts'' of Sept. 11 and its aftermath.

The FBI official confirmed that families of the crash victims will be allowed to listen to the audio recordings in Princeton, N.J., on April 18. The flight, which crashed in a field in Shanksville, Pa., had departed earlier in the day from Newark, N.J., for San Francisco. It had turned mid-flight and apparently was headed toward Washington when it went down.

The San Francisco Chronicle first reported the FBI's offer in this weekend's editions.

Alice Hoglan, whose son, Mark Bingham, 31, died on the flight, told the Chronicle, ``I think Mueller is correct when he says we won't be consoled by it. It is awful. But it is like something you have to do — I need to get clarity and perhaps hear my son's voice.'' she said.

Deena Burnett, whose husband Tom Burnett, 38, called her from the airplane and said he and some other passengers were going to try to take back control of the jet, told the newspaper she was told she would be able to listen to the recording, ask questions, and then the FBI would play it a second time.