CLEVELAND -- The definition of an air traffic controller is in the title. They control air traffic.

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But on Sept. 11, they -- like many of us -- lost control.

Now they too are hurting.

NewsChannel5's chief investigative reporter Duane Pohlman traveled to Baltimore to talk with one man who counsels air traffic controllers. He has the inside story of their crisis.

Dr. Jeff Mitchell:
"You have a maverick aircraft that is not responding to radio communication.

"Now we've got two. Wait a minute! There's three. Wow! There's another that are not acting properly. That produces a massive degree of confusion."

Duane Pohlman:
Mitchell knows a lot about confusion, chaos and crises. Mitchell, a professor at the University of Maryland-Baltimore, founded the International Critical Incident Stress Foundation.

For almost three decades, Mitchell has trained everyone from the CIA to firefighters on how best to deal with stress following a catastrophe.

He trained air traffic controllers, too. Though nothing could prepare them for Sept. 11.

Dr. Jeff Mitchell:
"They've tried to communicate repeatedly with the aircraft. That's not working and they can't figure it out. So they're scrambling frantically."

Duane Pohlman:
In the midst of that frantic scramble, air traffic controllers at Cleveland Center watched as the fourth plane, flight 93, made an unexpected turn over the skies of Ohio.

As the drama continued to unfold, controllers heard some of the voices and violence.

Dr. Jeff Mitchell:
"As the terrorists were keying mics on board the aircraft, some of the things they were saying, either to the people on board or to others, was coming out over the air."

Duane Pohlman:
The president of the Air Traffic Controllers Association says that the controllers could only listen helplessly.

John Carr - National Air Traffic Controllers Association:
"We have men and women who heard things no one should ever have to hear, who saw things no one should ever have to see, and we've got some people who are hurting."

Duane Pohlman:
That hurting is where Mitchell comes in.

Teams of air traffic controllers that he trained are now counseling and comforting colleagues who took the tragedies very personally.

"When they talk with you, what words do they use to describe it?"

Dr. Jeff Mitchell:
"They're using words like unbelievable, out of control, because it wasn't a thing they could control. You can't reach up and turn the plan around and aim it in a different direction."

Duane Pohlman:
Yet even in the midst of the darkest day in aviation, the controllers managed to re-direct thousands of other planes to land, possibly averting other tragedies.

"If you could make any one statement to air traffic controllers, what would it be?"

Dr. Jeff Mitchell:
They saved many, many lives. They may not see that when they're looking at the scope, but that's what they need to know. That they've done an incredible job under extraordinarily awful circumstance.

"They can recover, just like America can recover from this."