"Sept. 11 literally was just a normal day for us," says Col. Mark Tillman, remembering that morning.
Millions of Americans can say that. But only one can say his job that day was flying the President of the United States as the pilot of Air Force One. Col. Tillman found out about 9/11 as many of us did, by watching the news.
"The plane was getting ready to go and then when I was actually on the aircraft, the radio operator called me and said 'Hey you need to come upstairs right away; take a good look what I have on the television right now.'"
He watched the unfolding horror on a television on the president's plane.
It was after the second plane hit that they knew something was terribly wrong.
"It was at that point that we realized that something was occurring, was going wrong. At that point also, our radios to all the different agencies started coming alive," he recalls, and says his goal was then to get President Bush, who was reading to a second-grade class at a nearby Sarasota, Fla., elementary school, safely back home.
"We got word that there were about nine aircraft that had been hijacked, that's what we were passed from the Secret Service channels and everything else. We were trying to figure out exactly whether we were about to be under attack, whether we were a part of it. No one really knew, so the plan for us was get the plane moving as quick as possible because sitting on the Sarasota tarmac I was just a big target, a 747...We are a sitting duck."
So Tillman awaited his passenger, President Bush, who quickly arrived and wanted to immediately fly back to Washington.
"In the cockpit I look out, that's my job, is to watch him come up the stairs and make sure he gets up safely. So I watched him come, he came up the stairs, all business; he came to the top of the aircraft and came on board. At that time we had the right engines running."
Col. Tillman didn't know it, but that was the beginning of an unexpected journey, filled with various, alarming threats. The first came even before he took off. The Secret Service reported an unidentified man with some type of device, standing by the fence at the end of the Sarasota runway. So Tillman deviated from standard procedure, and decided to take off in a different direction.
"We assumed everybody was a threat. They asked if I could not taxi by him, take off in the opposite direction. They didn't know what the gentleman had, but he had something in his hand, they thought it might have been a long gun... I took off opposite direction and just rotated fairly quickly, got the plane climbing out as much as it can climb out then turned away about mid-field so the gentleman just wouldn't have a shot at us at all.... As it turned out, the gentleman was just a guy taking pictures at the end of the runway."
But at that early point, it didn't seem as if the skies were safe either. The air controllers told Col. Tillman that it appeared that another aircraft was following Air Force One.
"As we got over Gainesville, Fla., we got the word from Jacksonville Center. They said, 'Air Force One you have traffic behind you and basically above you that is descending into you, we are not in contact with them -- they have shut their responder off.' And at that time it kind of led us to believe maybe someone was coming into us in Sarasota, they saw us take off, they just stayed high and are following us at this point. We had no idea what the capabilities of the terrorist were at that point."
Col. Tillman was taking no chances.
"It was kind of the classic response of the terrorists that day that were hijacking airliners," says Tillman. So he decided to see if he indeed was being followed. He turned out into the Gulf of Mexico to see if the mysterious plane would do the same. It did not, and turned out to be an innocent airliner that had lost its transponder, and the pilots hadn't switched to the correct frequency to talk to controllers.
But the possible danger wasn't over. Once Col. Tillman determined that plane was not a threat, he received an ominous message.
"We got word from the vice president and the staff that 'Angel was next,' Angel being the classified call sign of Air Force One."
"Once we got into the Gulf and they passed to us that 'Angel was next,' at that point I asked for fighter support. If an airliner was part of the attack, it would be good to have fighters on the wing to go ahead and take care of us."
It turned out that the message was erroneous, but the decision was made not to fly back to Washington, D.C., as controllers were unsure about how many hijacked aircraft were still in the air.
Col. Tillman flew the president to Air Force bases in Louisiana and Nebraska, where the commander in chief addressed the nation and could communicate with military leaders from the ground.
As the day wore on and U.S. airspace was closed, the skies were nearly empty. "It was very eerie," Col. Tillman recalls. "No radio calls; the controllers would not even talk with us.
"Basically, they were told to just let us do what we wanted to do. We would tell them we were climbing to a certain altitude, and had given them a cardinal direction to where we were headed, but for the most part there was no conversation so no one knew where we were. There were no other aircraft talking except for a couple of military aircraft … planes just weren't flying; it was very eerie for the United States of America."
As the day neared an end and it came time to take the president home to Washington, D.C., Col. Tillman faced possibly the most stressful part of his journey.
"They were rolling fighters off the major cities to roll in on us to support us as we came across country. As we got closer to Washington, D.C., the concern was had I done everything I was supposed to do, to make sure that when I landed there everything would be safe?"
Col. Tillman thought the terrorists could be waiting.
"All along, everybody knew I was bringing him home, so my fear was they've done all of this, they know Air Force One is eventually going to come back to Washington, D.C.; they are sitting there, they're waiting for us."
The fighter jets stayed with the plane all the way.
"That's what the whole military and the United States Air Force is about. To see a fighter roll up on the wing, and salute you, get you right there and protect you as you're coming in -- that capability is tremendous."
But, Tillman says, as they approached Andrews Air Force Base, the damaged Pentagon was clearly visible.
"The whole day came into perspective at that point. You know, I had been evading so-called threats the whole day long, keeping him safe and now was the big finale. I had to make sure we got him in there, he stayed safe so he could get back to the White House."
After one of the most dramatic of all days, Air Force One landed home safely.
"Our job was to take care of the president of the United States. We'd been trained to keep him safe and that's what we were executing that day," says Tillman proudly. He went on to serve as the Air Force One pilot throughout the Bush term, retiring in 2009. His last flight at the controls of Air Force One was when he flew President Bush to Crawford, Texas, the day President Obama was inaugurated.
He now flies the president of an American corporation, albeit in a much smaller jet.
For Col. Tillman, the lessons of that day a decade ago remain.
"I'm a strong believer that there will be other attacks," predicts Tillman. "They caught us with our pants down, they attacked our country, they attacked from within... You got to assume right now that they're going to go ahead and infiltrate us and they're going to go ahead, take advantage of everything we offer to them. ...I think President Bush did a great job making sure the American people realize our safety is important, but we've got to go ahead and protect each and every one of us, take care of each other and change the way we do business so the terrorists won't take advantage of us anymore."
Eric Shawn is a New York-based anchor and senior correspondent for FOX News Channel (FNC). He anchors "America's News Headquarters" on Sundays from 12 p.m. to 1 p.m. ET. and “Sunday Morning Futures with Maria Bartiromo.” He anchors frequently during the week on the Fox News Channel and reports on politics, terrorism, and foreign affairs. Shawn has provided live coverage from both the Democratic and Republican National Conventions since 1992. In 2004 he led the Fox News investigative team that uncovered new evidence in the murder of Jimmy Hoffa, based on the claims of hit-man Frank Sheeran. Click here for more information on Eric Shawn.