2 Southwest planes came within 500 feet in close call near Nashville airport

Two Southwest Airlines flights had a close call on Saturday near Nashville International Airport as an aborted landing brought one plane into the direct path of another jet that was taking off.

Gusty winds near the airport forced the pilots of flight 507 from Myrtle Beach, South Carolina, to abort their landing and execute a go-around at about 5:30 p.m. local time. Air traffic control told the pilots to turn right, which put them on a potential collision course with another 737 that had been cleared for takeoff from a parallel runway.

Both planes' Traffic Collision Avoidance Systems ordered the pilots to take evasive maneuvers. Preliminary flight data appears to show the plane that was taking off, flight 1152 to Knoxville, Tennessee, essentially flew right over flight 507 with only around 500 feet of altitude between them.

Both flights landed safely at their intended desitnations. 

"Southwest appreciates the professionalism of its Pilots and Flight Crews in responding to the event," the airline said in a statement. "Nothing is more important to Southwest than the Safety of our Customers and Employees."

The FAA in a statement acknowledged that air traffic control's instructions put flight 507 "in the path of another airplane," and said it was investigating the incident.

Aviation safety analyst Robert Sumwalt told CBS News that the Traffic Collision Avoidance System, known as TCAS, is "one of the last lines of defense to keep airplanes from coming together."

Last summer, CBS News was able to see how TCAS works in a flight simulator. If a plane isn't a safe distance from another aircraft, the TCAS would send a command to the flight deck.

For example, pilot Miles Morgan explained to us, "If my aircraft was told to descend, that [other] aircraft would be told to climb, and that would increase the separation."