Since the Sept. 11, 2001 attacks most Americans understand the nation's air traffic controllers serve a critical role by protecting those in the air and our national security. So how can an air traffic control supervisor at the Federal Aviation Administration's Denver Center have sex with a subordinate while on duty and still keep his job?7NEWS Investigators have learned that this is only one of several serious incidents involving the supervisor. The FAA management of the Denver Center, which is located in Longmont, has known about a continuing pattern of questionable behavior that has gone on for years, said 7NEWS Investigator John Ferrugia.What's more, managers know that, when questioned, the supervisor lied about it. Yet Paul Conway still has his job.Conway is a longtime air traffic control supervisor who manages controllers at what is known as the Denver Center. This center controls 285,000 square miles -- portions of nine states -- and, at any given moment the lives of thousands of air travelers.In the high-pressure job, controllers must be alert and focused as they are often directing several aircraft at once through airspace teeming with traffic.According to FAA documents, Conway is attentive, but his focus isn't always on the airplanes. The FAA has known that as far back as 1997, Conway has been involved with women who are his subordinates -- both on duty and off duty.A transcript obtained by 7NEWS shows one of his subordinates describing sexual activity with Conway in his office while both were on duty."At that time, we also began seeing each other after the 3-11 shift," she said in the transcript.The female controller later complained of harassment once she ended the affair.When asked to talk about his conduct at work at the FAA, Conway said, "I have no comment my conduct at work is my conduct at work."FAA documents show that in 2003 there was another affair as Conway "developed a personal relationship of a sexual nature with a former subordinate who was temporarily assigned to a staff position."The reports said the woman "was married to another employee" at the center. The husband of the woman still works there."Do you think I should be paying for your salary, the taxpayers should be paying for this kind of conduct from a manager at an air traffic control center?" Ferrugia asked Conway."Mr. Ferrugia, I think I've made it very clear to you, I have nothing to say to you. Thank you for your time," Conway said.A third documented incident showed that Conway made an inappropriate approach to a young "developmental controller experiencing a traumatic situation in her personal life."The activity stopped when Conway's wife called the woman.Rep. Mark Udall was clearly stunned by the FAA reports."It's about air travel safety and then you put in the mix, John, the moral issues and people literally looking over their shoulders. When it comes to that supervisor, I just don't understand why this behavior would be tolerated and a suspension makes no sense," Udall said.Conway was suspended but is still a supervisor. According to documents, even though FAA managers knew about the long history of inappropriate behavior, in 2005 they only recommended a 14-day suspension."That's a minor penalty particularly given the pattern of misbehavior that this gentleman's involved himself in. So it makes no sense to me. That's not even a slap on the wrist from what I can tell," said Udall.Records also show that when Conway was confronted with the facts and allegations, he lied about it to his FAA bosses."Your dishonesty makes resolution of these matters even more difficult ... Although your behavior has been inappropriate, your inability to consistently tell the truth is even more troubling," the report said.Udall wants answers from the FAA and he isn't the only one.After reviewing 7NEWS' findings, Sen. Wayne Allard sent a letter to the Department of Transportation which reads in part, "Inappropriate sexual behavior in the workplace is inexcusable. Inappropriate behavior at the FAA, an agency charged with protecting the lives of tens-of-thousands of people, is particularly troubling."The air control center is in the Congressional district of Marilyn Musgrave. In a letter to the head of the FAA, she calls for an immediate investigation, writing, "I want to know why employment policies at the FAA have allowed this interoffice behavior to continue and why this employee has been allowed to remain employed with a salary of more than $150,000 annually." The FAA said this is a personnel matter and privacy laws keep officials from commenting. Have a comment or question about this story? E-mail the Investigators or call 303-832-TIPS.