What types of airspace classifications are included in the National Airspace System?

The correct choice is based on the classification of airspace within the National Airspace System (NAS), which categorizes airspace to ensure the safety and efficiency of air traffic. The comprehensive airspace classes include A, B, C, D, and E, each serving distinct purposes and operational requirements.

Class A airspace is high-altitude controlled airspace, typically extending from 18,000 feet up to 60,000 feet. Class B airspace surrounds the busiest airports and requires specific communication and equipment capabilities for aircraft to operate within it. Class C airspace also supports airports with significant traffic but has less stringent entry requirements than Class B. Class D provides air traffic control service to airports with smaller amounts of traffic, and Class E consists of various areas that are controlled and uncontrolled under certain conditions, typically existing below 18,000 feet.

This structured classification contributes to maintaining safe distances between aircraft, facilitating organized flight operations, and properly managing air traffic. Each category is essential for different types of operations, making it crucial to understand these elements for effective training and operational success in unmanned aircraft systems.