return from reading to a school class. after that, he said his only goal was to get the president back home safely, but that day, as we know, took several turns, all of them in the name of keeping our commander in chief safe. eric shaun with more on this. >> hi. they thought they were being chased by a hijacked airliner. unuseful, colonel mark tillman, air force one's pilot, faced a variety of potential threats. for starters, as they were about to take off, the secret service told him there was a suspicious man near the runway. >> it turns out the gentleman was just a guy taking pictures at the end of the runway. it was no threat whatsoever. but it encapsulated the whole day. that's what was going on. we found out later it was a threat. >> after takeoff, colonel tillman was told an airliner may be following air force one. >> there was a plane behind us, defending into us that is kind of unusual. they're not talking to us.