NARRATOR: September 11, 2001. A day of grief. A day of courage. This is how that day unfolded.

GEORGE TAMARO: My daughter called me. She said a plane just flew into the World Trade Center. Nah, you got to be kidding. It's got to be a pipe. [? A ?] cumbersome clown was flying down the river.

NARRATOR: At 8:46 AM American Airlines Flight 11 from Boston with 92 aboard. September 11, 2001. A day of grief. A day of courage. This is how that day unfolded.

GEORGE TAMARO: My daughter called me. She said a plane just flew into the World Trade Center. No, you got to be kidding. It's got to be a [? pipe. A ?] cumbersome clown was flying down the river.

NARRATOR: At 8:46 AM American Airlines Flight 11 from Boston with 92 aboard, traveling at a speed of 470 miles per hour, strikes the North Tower of the World Trade Center complex. Within minutes, officials coordinate the citywide emergency response. Their base of operations is a state of the art command center located on the 23rd floor of 7 World Trade Center.

With one tower in flames, the tragedy is only beginning. It is 9:03 when United Airlines Flight 175 with 65 aboard, traveling at the speed of 590 miles per hour, smashes into the South Tower of the World Trade Center. This aircraft strikes the corner of the South Tower. It rips a diagonally shaped gash from the 84th to the 78th floors. The South Tower lasts only 56 minutes before it succumbs at 9:59 AM. The dust cloud billows outward for blocks. Victims stagger away. At 10:28, the television mast atop the North Tower spears straight down.

W. GENE CORLEY: Once the collapse started, there really wasn't any way to stop it. It was just going to go all the way down once it got started.

NARRATOR: Chaos in New York City. Power is down in Lower Manhattan. Phone lines jammed with more than 230 million calls. Hundreds of firefighters trapped in the towers. Hundreds more raced to the scene.

Falling debris from the collapse of the North and South towers ignites fires in the neighboring buildings of the World Trade Center. World Trade 4, 5, and 6 are ablaze. World Trade 7, the building housing the city's command center, burns unchecked for seven hours. At 5:20, it collapses. The city's emergency nerve center is destroyed.

RICHARD J. SHEIRER: Somewhere in that time-- and it's very hard to keep track of time during this-- they had been ordered to evacuate Number 7 by the Port Authority. To this day, we don't know who gave that order, but whoever it was saved a lot of people's lives.

NARRATOR: With New York a war zone, some residents walk across the Brooklyn Bridge to get out of the city. Others seek escape in vessels piloted by the Army Corps of Engineers. At 7:45 PM, the New York Police Department says 78 officers are missing and estimates that 200 firefighters are dead. At 10:56 PM, police officials say they believe there are victims alive in the rubble of the World Trade Center.

RICHARD BIGGS: Working with urban search and rescue teams, there was a lot of areas to be searched underneath the debris field. There were voids that had to be searched for possible live people.

NARRATOR: September 11, 2001, the longest and most tragic day in New York's history is drawing to a close.

NARRATOR: 9:03 AM, 17 minutes after the attack on the World Trade Center began, a second plane crashed into the South Tower. Fire Chief Richard Picciatto arrived just after the second plane hit. He was told people need assistance on the 25th floor of the North Tower. By now, hundreds of firefighters and other rescue workers were rushing up the stairs in an attempt to save those who were trapped.

RICHARD PICCIATTO: All of a sudden, this noise starts, this horrendous noise. It's coming from above us. It's really loud. It's powerful. Sounds like something's crashing through the floors above us. It just froze us we all just froze our steps looking up wondering what is this.

NARRATOR: The collapse of the South Tower wasn't visible to people inside the stairwells of the North Tower. Fire Chief Richard Picciotto was on the 35th floor when the lights failed. Up above, police helicopters could see what was happening to the surviving tower. They quickly passed this information down to their colleagues on the ground.

DISPATCH: The remaining tower, the North Tower is leaning to the southwest at this time. It appears to be buckling in the southwest corner.

JIM DWYER: That message got communicated down to the police officers. A number of them were inside the building. Some of them were on the street. And people were getting told to pull back, pull back, pull back.

NARRATOR: Fire Chief Richard Picciato was one of the few firefighters who did hear the order to get out.

RICHARD PICCIATO: We're getting out. And I went to all three stairwells-- just three stairwells in the building-- yelled up and down for people to get out. Floor by floor, I was doing a quick sweep to try to make sure no one was left behind.

NARRATOR: It was 10:26. The North Tower was moments from collapse.

RICHARD PICCIATO: I got down to approximately the sixth floor of the building was shaken more lights went out. Didn't know what was happening. I knew the building was collapsing. It took eight seconds for the North Tower to collapse. I tell people there's a lot of things you could think about in eight seconds. It's not really a lot you could do.

NARRATOR: As the floors pancaked onwards, Fire Chief Picciato's group began falling inside the collapsing tower.

RICHARD PICCIATO: The building was shaking. We were getting tossed around. And then the stairs went out from under me. And I started tumbling and falling. I'm laying in total darkness, total silence. And at first, I thought I was dead. But I had the sense that there were other people there. So I called out, is anyone else here? And I started to get a few responses. Yeah, I'm here. I'm here too.

NARRATOR: Miraculously, the 12 firemen and the disabled woman they'd been carrying lay battered but alive in the remains of the stairway. They had survived the collapse of 107 floors but were now encased in debris in what they feared would become their tomb. From under the ruins, Fire Chief Picciatto continued to try to make contact with the outside world.

RICHARD PICCIATO: I think it was approximately an hour and a half I was calling until someone answered me back. And I told him we're in the B stairway, the North Tower of the B stairway, approximate the third floor. That's where I originally was, about the third floor. And his first response back was, where's the North Tower?

NARRATOR: The devastation was such that rescue workers couldn't even tell where the tower had been. It was another three hours before Richard Picciotto got out.

RICHARD PICCIATO: There was this crevice leading up through all this debris. So I climbed up and followed the light. And all of a sudden, I was on top of this-- I was out on the rubble field, I was on this huge pile. I was at the top of it. All I could see was just devastation and buildings on fire, like what you would picture in the remnants of the nuclear war.

SPEAKER 1: One report said-- and we can't confirm any of this-- that a plane may have hit one of the two towers of the World Trade Center.

[SIRENS]

SPEAKER 2: Oh my god.

SPEAKER 3: That looks like a second plane.

[SHOUTING]

SPEAKER 4: Our belief at the moment is that an aircraft has crashed into the Pentagon.

SPEAKER 5: By 9:34 AM, it had become clear to air controllers that yet another plane had been hijacked. Then word started reaching the press.

JON MEYER: Across the scanner in our newsroom was said that there was a flight that was missing. There had been a flight that they thought was heading towards Pittsburgh or Johnstown, which is where I was. And they couldn't get in touch with it.

SPEAKER 5: They were talking about flight 93. It had changed direction, and was apparently now over Pennsylvania. All indications were that the plane was heading towards the nation's capital. But the hijackers had been careful to turn off the transponder, cutting all communication with air traffic control. From a plane near Cleveland, a call came into the GTE phone center. It was particularly alarming.

LISA JEFFERSON: When I took over the call, there was a gentleman on the line-- very soft spoken, calm.

SPEAKER 5: The soft spoken gentleman was Todd Beamer, a passenger on United 93.

LISA JEFFERSON: I asked him to explain to me in detail what is happening on the plane. He told me there were three people that was taking over the flight.

JON MEYER: They tied red bandannas around their head, got up, and that that was when they forced their way into the cabin.

SPEAKER 5: But when the hijackers stormed the cockpit, nobody on flight 93 was primed to stop them.

JON MEYER: Prior to September 11, the way flight attendants were trained on a plane was to listen to the hijackers, to stay calm, and to comply with what their demands were.

SPEAKER 5: Unreleased recordings indicate a struggle in the cockpit.

JOHN NANCE: Well, in the cockpit, I think that what happened is the pilots had been subdued. I think their necks had been slashed. And they're strapped down.

They've got no way of defending themselves. You can't turn around and fight. They're just sitting ducks.

SPEAKER 5: But it only got worse. From the hijackers, there was a horrifying announcement.

JON MEYER: The hijackers on the intercom saying, there's a bomb on board. We have control of this plane. We're going back to the airport.

SPEAKER 5: On the air phone, Todd Beamer had informed operator Lisa Jefferson about the hijackers' tactics.

LISA JEFFERSON: He told me that they've taken control of the plane. The plane is going down. At this point, he raised his voice. He said, we're going down. We're going down.

No, we're coming back up. Wait, we're turning around. We're going back north. I think we're going north. At this point, I don't know where we're going.

SPEAKER 5: In fact they had turned around, and were now going east. At 9:35, it appeared that the hijackers were headed for Washington D.C. But this was no ordinary hijacking. The attack on the World Trade Center would soon become known to the passengers on flight 93, who called relatives.

JON MEYER: And that's when they knew that this plane wasn't just being flown back to an airport. Once those people on board that plane knew it, there was-- they knew there was no going back. This was the new reality of what we face now. They were the first ones they realized they needed to do something.

SPEAKER 5: In the air above Pennsylvania, a plot was brewing.

LISA JEFFERSON: Todd told me that him and a few other guys were thinking about jumping the guy with the bomb. He felt that he had to do-- to try to save the plane, or at least try to get the plane to land safely. And I told him that he had every hope, and I had hope for him that they could land the plane safely.

He turned from me to speak to someone else. And he said, are you ready? I couldn't hear their response. He said, OK. Let's roll. That's the last I heard from Todd Beamer.

The line was still open, but it was very silent. I didn't hear anything else. I kept that phone line open for about 15 additional minutes.

And while our operation center was tracking the call, we heard that the plane had crashed in Pittsburgh. And I knew that was his flight. I felt that I had just lost a good friend.

SPEAKER 5: A 35 foot deep pit in Pennsylvania became the grave of everybody on flight 93.

JON MEYER: People were drawn to flight 93 because they felt those people on board were the first warriors in the battle against terrorism. And that's a theme you see in this temporary memorial over and over again in the messages people leave. Thank you for fighting back.

Thank you for starting this fight against terrorists. I think people have thought that through and thought, would I do that? These people did something special.

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