During an instrument precision approach, what does terrain and obstacle clearance depend on?

During an instrument precision approach, terrain and obstacle clearance depend primarily on the minimum altitude shown on the Instrument Approach Procedure (IAP). This altitude is explicitly designed to ensure that aircraft maintain a safe distance above the terrain and any obstacles in the approach path. The IAP provides crucial information, including the minimum safe altitude for various segments of the approach, which is derived from detailed surveys and safety considerations to protect against potential hazards.

The specified minimum altitude also incorporates factors like the specific approach type and the related airspace characteristics, allowing pilots to execute the approach safely. By adhering to these altitudes, pilots ensure that they remain clear of terrain and obstacles during the critical phases of the approach and landing.

Current weather conditions may influence the approach decisions, but they do not change the established minimum altitudes necessary for terrain and obstacle clearance. Similarly, while the type of aircraft and the area of operation can affect other aspects of flight, they do not dictate the minimum altitudes required for safe approach clearance outlined in the IAP.