I noticed a few posts on other forums, from people new to the Agency, regarding the term “Good Time”. I wanted to take a moment to point those with questions in the right direction for answers. From employees.faa.gov:

An Air Traffic Control (ATC) Specialist is defined as a civilian employee who is actively engaged: in the separation and control of air traffic; or providing pre-flight, in-flight, or airport advisory service to aircraft operators. Also included in this definition is an employee who is the immediate (first-level) supervisor of an air traffic controller as defined above. The Secretary of Transportation makes this determination. This is also referred to as "good time", "covered position", or "ATC time."

To be eligible for the special retirement computation, an employee must have occupied a position as defined above for 20 years and retire under the special retirement provisions.

For more info follow these links:

• Air Traffic Controllers and Retirement
• Air Traffic Controller Retirement Overview