Final answer:
When flying over congested areas, except during takeoff and landing, aircraft must maintain a minimum altitude. In congested areas, such as cities or towns, the minimum altitude is typically set at 1,000 feet above any obstacles. This ensures the safety of both the aircraft and the people and property on the ground.
Step-by-step explanation:
When flying over congested areas, except during takeoff and landing, aircraft are required to maintain a minimum altitude. The specific altitude that must be maintained depends on the regulations of the governing aviation authority. In the United States, for example, the Federal Aviation Administration (FAA) mandates that aircraft must maintain an altitude of at least 1,000 feet above any obstacles in congested areas, such as cities or towns.
This minimum altitude ensures the safety of both the aircraft and the people and property on the ground. It allows for a margin of error in case of any unexpected events or emergencies during flight. By maintaining a sufficient altitude, the risk of collision with buildings, vehicles, or people on the ground is minimized.
To further ensure safety during flight, the FAA also enforces specific separation distances between aircraft. This includes maintaining a certain distance from other planes flying at the same altitude and maintaining vertical separation to avoid any potential mid-air collisions.