But, the investigation took a whole new turn when we interviewed a veteran RDU air traffic controller.
Air traffic controllers at RDU handle more than 325,000 flights a year and they say it's a stressful job.
"You feel physical fatigue, you feel mental fatigue," says John Brown. He's been an air traffic controller at RDU for twenty years. "It's just an incredible amount of responsibility," says Brown.
Brown is also the local air traffic controller union representative.
"The level of safety is just not there," Brown says about the RDU control tower.
We found some evidence of that when we checked out the Aviation Safety Reporting System. It's a database run by NASA that compiles anonymous complaints from pilots and air traffic controllers.
Last February, a RDU controller cleared a Boeing 737 for take off. Seconds later, it nearly collided with a medi-vac helicopter over Wake County. In fact, there are multiple entries in recent years from pilots who say conflicting instructions from controllers put them right in the path of other airplanes.
"I can tell you there are incidents on a daily basis that are levels of safety that occur for one reason or another," says John Brown.
In an entry from 2006, a controller complains a radar equipment problem is "very much a safety issue." In the database, we also uncovered a question about staffing in the tower. In 2006, an airline captain reported an incident where one controller had to manage three different radio frequencies at the same time.
"We have a reduced margin of safety just because we don't have enough experienced eyes watching the skies," says John Brown.
The FAA admits there are fewer "fully certified" controllers at RDU than it should have but it believes the problem will be corrected in the years ahead when trainees become certified.
"You have a fewer number of controllers responsible for more airplanes," says John Brown, describing the air traffic control situation at RDU.
Brown also says RDU controllers have been begging the FAA for a radar system that lets them see planes on the ground when there's reduced visibility.
"I have seen instances where a vehicle, because we couldn't see him, from the tower or an aircraft got somewhere where he wasn't supposed to be and put him in a proximity that was too close to an aircraft landing or taking off," says Brown.
"You've had near misses on the ground that could have been avoided?" asked Steve Daniels.
"I wouldn't classify it as a near miss, so much as a reduced level of safety and a situation that could have been a problem, a catastrophic event," replied Brown.
Steve Daniels asked, "Are you trying to frighten people because you want new contract, you want more money?"
"I'm not trying to frighten people," said Brown. "I believe that people should take note of what other people are saying, listen to what the pilots are saying, the references you made about different, I mean, you're just scratching the surface on what happens on a daily basis," continued Brown.
Another issue at RDU we discovered in this NASA database is low morale. An RDU controller warns that the workplace is "oppressive" and "hostile" writing, "Be advised, it is affecting safety. Everyday I see controllers totally distracted by what is happening. Someone is going to die as a result."
"The flying public needs to understand that a safety related service needs to have multiple layers of safety, every time they get on the airplane," says John Brown. He continued, "I mean, that's what I want for my family when they fly. That's what I want when I fly."
The FAA says currently we are experiencing the safest period in aviation history on record. FAA, as are the air traffic controllers that guide some 7,000 aircraft aloft the U.S. at any one time, are committed to making the national air space the safest, most efficient in the world.