What are Class E base options around airports with instrument approaches?

• A. Surface, 700 ft AGL, or 1200 ft AGL bases.
• B. Surface, 500 ft AGL, or 1000 ft AGL bases.
• C. Surface, 900 ft AGL, or 1500 ft AGL bases.
• D. 700 ft AGL, 1200 ft AGL, or 1800 ft AGL bases.

Answer: (A)

Class E base options around airports with instrument approaches determine where controlled airspace begins to protect IFR operations. When an airport has instrument procedures that require protection close to the ground, Class E can begin at the surface. More commonly, the base is 700 feet AGL to provide controlled airspace for IFR traffic in the terminal area without extending all the way to the surface. In many cases, the base is 1,200 feet AGL, which still confines IFR procedures within controlled airspace while allowing more space below for VFR activities. These three bases—surface, 700 feet AGL, and 1,200 feet AGL—are the standard options used for airports with instrument approaches. Other base elevations like 500, 900, 1,500, or 1,800 feet AGL aren’t the standard classifications for this context.