What is the significance of the base of Class E airspace in many locations?

The base of Class E airspace is often significant because it typically starts at 1,200 feet AGL (Above Ground Level) in many locations. This altitude has been established to provide a buffer zone where the airspace transitions from uncontrolled to controlled, allowing for safe navigation and communication for both visual and instrument flight rules.

The 1,200 feet AGL starting point plays a crucial role in separating high-density traffic airspace from lower, uncontrolled airspace, particularly for general aviation. This is important to ensure that pilots flying VFR (Visual Flight Rules) can operate safely without encountering IFR (Instrument Flight Rules) traffic unexpectedly.

Understanding this baseline allows pilots to comprehend where airspace transition points exist, aiding in flight planning and situational awareness. While specific locations may have variations (such as airspace that starts lower than 1,200 feet due to special circumstances), the general rule serves a critical function in aviation safety management.