How much clearance is specified for altitude above obstacles near the route centerline?

The specified clearance for altitude above obstacles near the route centerline is 1,000 feet. This standard is set to ensure that aircraft maintain a safe altitude over various obstacles, providing a significant margin for safety in case of turbulence or other unforeseen circumstances.

The requirement for 1,000 feet of clearance is particularly relevant in areas with varying terrain, ensuring that aircraft can operate safely without the risk of collision with obstacles such as towers, buildings, or terrain features. This altitude is a crucial aspect of vertical navigation, especially in the context of instrument flight rules (IFR), where reliable altitude minima are necessary for the safe operation of flights along specific airways and routes. The clearance provides sufficient vertical separation from potential hazards below the aircraft, contributing to overall airspace safety.