For one instant on the morning of September 11, an airliner that had vanished from all the tracking tools of modern aviation suddenly became visible in its final seconds to the people who had been trying to find it.
It was just after 9 am, 16 minutes after a plane had hit the north tower of the World Trade Centre, when a radio transmission came into the New York air traffic control radar center. "Hey, can you look out your window right now?" the caller said.
"Yeah," the radar control manager said.
"Can you, can you see a guy at about 4,000 feet, about 5 east of the airport right now, looks like he's -"
"Yeah, I see him," the manager said.
"Do you see that guy, look, is he descending into the building also?" the caller asked.
"He's descending really quick too, yeah," the manager said. "Forty-five hundred right now, he just dropped 800 feet in like, like one, one sweep."
"What kind of airplane is that, can you guys tell?"
"I don't know, I'll read it out in a minute," the manager said.
There was no time to read it out.
In the background, people can be heard shouting: "Another one just hit the building. Wow. Another one just hit it hard. Another one just hit the World Trade."
The manager spoke.
"The whole building just came apart," he said.
That moment is part of a newly published chronicle of the civil and military aviation responses to the hijackings that originally had been prepared by investigators for the 9/11 Commission, but never completed or released.
Threaded into vivid narratives covering each of the four airliners, the multimedia document contains 114 recordings of air traffic controllers, military aviation officers, airline and fighter jet pilots, as well as two of the hijackers, stretching across two hours of the morning of Sept. 11, 2001.
Though some of the audio has emerged over the years, mainly through public hearings and a federal criminal trial, the report provides a rare 360-degree view of events that were unfolding at high speed across the Northeast in the skies and on the ground. This week, the complete document, with recordings, is being published for the first time by the Rutgers Law Review, and selections of it are available online at nytimes.com.
"The story of the day, of 9/11 itself, is best told in the voices of 9/11," said Miles Kara, a retired Army colonel and an investigator for the commission who studied the events of that morning.
Most of the work on the document - which commission staff members called an "audio monograph" - was finished in 2004, not in time to go through a long legal review before the commission was shut down that August.
Mr. Kara tracked down the original electronic files earlier this year in the National Archives and finished reviewing and transcribing them with help from law students and John J. Farmer Jr., the dean of Rutgers Law School, who served as senior counsel to the commission.
At hearings in 2003 and 2004, the 9/11 Commission played some of the recordings and said civil and military controllers improvised responses to attacks they had never trained for. At 9 a.m., a manager of air traffic control in New York called Federal Aviation Administration headquarters in Herndon, Va., trying to find out if the civil aviation officials were working with the military.
"Do you know if anyone down there has done any coordination to scramble fighter-type airplanes?" the manager asked, continuing: "We have several situations going, going on here, it is escalating big, big time, and we need to get the military involved with us."
One plane had already crashed into the north tower of the World Trade Center. Another had been hijacked and was seconds from hitting the south tower. At F.A.A. headquarters, not everyone was up to speed.
"Just get me somebody who has the authority to get military in the air, now," the manager said.
In its 2004 report, the commission praised front-line aviation officials. But it then thoroughly dismantled the accounts of senior government officials, who in the weeks after Sept. 11, and for more than a year afterward, assured the public that fighter pilots had been in hot pursuit of the suicidal hijackers. During these chases, according to accounts from Vice President Dick Cheney, the F.A.A. and the Defense Department, the pilots were described as ready to carry out a wrenching order from President George W. Bush to shoot down airliners.
The commission discovered that little of that was true: of the four flights, military commanders had nine minutes' notice on one before it flew into the World Trade Center, and did not learn the other three had been hijacked until after they had crashed. Military commanders, given an order outside the chain of command to shoot down hijacked airliners, did not pass it along to the fighter pilots, but instructed them instead to identify the tail numbers of any suspected rogue planes. That turned out to be a prudent call because by then, there were no longer hijackers in the air for them to shoot.
The newly published multimedia document spells out precisely how the recordings contradicted the accounts of the senior officials.
Throughout the recordings, listeners also get a visceral feeling for the desperate scramble for information, as well as the confusion and lack of coordination between the civil and military aviation authorities. One example is an exchange that began at 9:34 am.
A military aviation official contacted the Washington center of the F.A.A. to discuss the situation, and learned, to her surprise, that American Airlines Flight 77 had disappeared more than 30 minutes earlier. No one had told the military.
"They lost radar with him, they lost contact with him, they lost everything, and they don't have any idea where he is or what happened," an unidentified F.A.A. official said. The plane was a 767, he said, explaining that he had gotten his information from the F.A.A.'s Indianapolis center.
"All I need is the lat-long, last known position of the 767," the military officer asked.
"Well, I don't know," the F.A.A. official replied. "That was Boston, that was Indy Center. But they said somewhere, it was, last time I talked to them, they said that it was east of York. And I don't even know what state that is."
Flight 77 crashed into the Pentagon three minutes later.
At almost the same time, a military commander, Maj. Kevin Nasypany, discovered that some of the fighter pilots had been sent east of Washington, over the ocean, in pursuit of American Airlines Flight 11 - which had crashed nearly an hour earlier into the north tower of the World Trade Center.
Major Nasypany ordered them to head toward Washington at high speed. "I don't care how many windows you break," he said.
The account published this week is missing two essential pieces that remain restricted or classified, according to Mr. Kara. One is about 30 minutes of the cockpit recording of United Airlines Flight 93, which crashed into the ground after passengers tried to storm the cockpit as hijackers flew across Pennsylvania toward Washington, D.C. Families of some of those onboard have objected to the release of that recording, Mr. Kara said.
The other still-secret recording is of a high-level conference call that began at 9:28 and grew, over the course of the morning, to include senior figures like Mr. Cheney, Defense Secretary Donald H. Rumsfeld and the vice chairman of the Joint Chiefs of Staff, Gen. Richard B. Myers.
The recording was turned over to the National Security Council. The 9/11 Commission was not permitted to keep a copy of it or of the transcript, Mr. Kara said, and investigators were closely monitored when they listened to it. Mr. Kara said he believed that the only truly sensitive material on the recordings were small portions that concerned the provisions being made to continue government operations if the attacks took out some national leadership or facilities.
"There was a staffer who was designated to sit with us, who would stop and start the tape, in my estimation to mask continuity of operations," Mr. Kara said.
Nevertheless, he noted, the commission ended up with hours and hours of recordings that it initially did not have access to or had been told did not exist, a point Mr. Farmer echoed in the preface to the Rutgers Law Review article.
When the commission began taking testimony, military and civil aviation officials said "that no tapes were made, and we were told at one point that a technical malfunction would prevent us from hearing them," Mr. Farmer wrote. "If we had not pushed as hard as we did - ultimately persuading the commission to use its subpoena power to obtain the records - many of the critical conversations from that morning may have been lost to history."