Which statement describes Class E transition area boundaries?

• A. It begins at the surface and extends upward.
• B. It begins at 600 ft AGL.
• C. It is the same as Class D airspace.
• D. It begins at 700 or 1200 AGL before becoming standard Class E; used to transition from uncontrolled to controlled airspace.

Answer: (D)

Class E transition areas exist to provide a controlled airspace corridor for aircraft moving from the uncontrolled Class G into the controlled Class E around airports that have instrument procedures but don’t have a Class E surface area. Their lower boundary is fixed at either 700 feet AGL or 1,200 feet AGL, and the airspace above that boundary up to the base of the surrounding standard Class E continues as controlled airspace. This setup is specifically for easing the transition from uncontrolled to controlled airspace as you approach or depart airports with instrument procedures. Therefore, describing a TEA as beginning at 700 or 1,200 AGL and then becoming standard Class E correctly captures its purpose and boundaries. It’s not a surface-based area, it’s not the same as Class D, and 600 AGL isn’t a TEA base.