The third generation of Tracking and Data Relay Satellites will be launched aboard an Atlas V launch vehicle, produced and built by Lockheed Martin. In planning TDRS K and L, requirements were sent to the United Launch Alliance (ULA), a joint venture between Boeing and Lockheed Martin, to identify the best Expendable Launch Vehicle to launch TDRS into it's geo-synchronous orbit, 22,300 miles above earth's surface. It was found that the Lockheed Martin Atlas V best met the needs of TDRS K and L, and was chosen in March 2009 to be TDRS's Launch Vehicle.

For more information about the Atlas V, check out the ULA Website.