What is the minimum altitude for Class E airspace when designated in conjunction with an airport with an Instrument Approach Procedure (IAP)?

The minimum altitude for Class E airspace designated in conjunction with an airport that has an Instrument Approach Procedure (IAP) is 700 feet Above Ground Level (AGL). This altitude is specifically established to provide a safe vertical separation for aircraft operating under instrument flight rules (IFR) as they approach and depart from an airport with an IAP.

Class E airspace often has variable floor altitudes depending on the surrounding terrain and specific requirements of the area. When a Class E airspace is created to support IFR operations at an airport, it typically extends down to 700 feet AGL in order to allow for proper obstacle clearance for aircraft conducting approaches and departures.

This altitude helps ensure that aircraft can safely operate in the vicinity of the airport without interference from ground obstacles while still allowing for some maneuverability. Altitudes below this, such as 500 feet or 1,200 feet AGL, do not conform to the established minimums required for the safety of IFR operations near airports with IAPs.