The class of airspace that can have a TRSA is typically Class E airspace. TRSAs, or Terminal Radar Service Areas, are a type of airspace that is established around certain primary airports with a class “D” designation. They are designed to provide additional services and increased safety for pilots operating in the vicinity of these airports.
One important thing to note is that TRSAs are not classified as separate airspace classes themselves. Instead, they are overlaid on top of existing controlled airspace, which is typically Class E airspace. Class E airspace is controlled airspace that extends from the surface or a specific altitude, such as 700 feet or 1,200 feet above ground level (AGL), up to either 18,000 feet or the base of the overlying controlled airspace.
The purpose of establishing a TRSA is to enhance safety and efficiency of air traffic operations in the vicinity of certain airports. TRSAs are typically located around airports that have a high volume of instrument flight rules (IFR) or visual flight rules (VFR) traffic. By providing radar services within the TRSA, air traffic controllers can assist pilots in maintaining separation from other aircraft and provide traffic advisories.
In my own personal experience, I have flown in airspace that includes a TRSA. I remember flying into an airport with a class “D” designation and noticing the transition from uncontrolled airspace to the TRSA. As I entered the TRSA, I established communication with the local air traffic control facility and received radar services. The controllers were able to provide me with traffic advisories and help ensure that I maintained appropriate separation from other aircraft in the area.
It’s important to understand that TRSAs are not mandatory for pilots to enter or use. However, it is highly recommended to utilize the services provided within a TRSA, especially for pilots who may be less experienced or unfamiliar with the area. By working with air traffic controllers and utilizing the radar services available, pilots can enhance safety and situational awareness in the vicinity of these busy airports.
To summarize, TRSAs are overlaid on top of Class E airspace and provide additional radar services and safety benefits for pilots operating in the vicinity of certain primary airports with a class “D” designation. They are not a separate airspace class, but rather an enhancement to existing controlled airspace. Utilizing the services within a TRSA can greatly enhance safety and situational awareness for pilots in these busy areas.