What is the required clearance above the highest obstacle in relation to the Minimum Safe Altitude (MSA)?

The correct requirement for clearance above the highest obstacle in relation to the Minimum Safe Altitude (MSA) is 500 feet. This standard ensures that aircraft maintain a safe margin above obstacles, which can include buildings, terrain, or other structures that may pose a risk to aircraft during flight.

In implementing this clearance, the MSA serves as a guideline for pilots to navigate safely, particularly in areas that may not have comprehensive obstacle data or in cases where rapid navigation is necessary, such as in the event of instrumentation failure or other emergency scenarios. By allowing for a 500-foot buffer, pilots can avoid potential hazards effectively while also ensuring compliance with aviation safety regulations.

Understanding this height requirement is critical for flight planning and en-route navigation, as it helps mitigate the risks associated with flying at lower altitudes near varied terrain.