How does altitude affect the size of the protected airspace in a holding pattern?

In a holding pattern, the size of the protected airspace increases with altitude. This is primarily because the aircraft's flight path in a holding pattern generally remains consistent regardless of altitude, but the physical distance covered in the airspace increases as altitude rises.

At higher altitudes, the airspace must account for the wider radius of the holding pattern due to the three-dimensional aspects of flight. The standard holding pattern typically has a defined turn radius and leg length that remains constant, resulting in a larger volume of protected airspace as the altitude increases. This ensures adequate separation from other aircraft and hazards in the vicinity.

So, as a result, higher altitudes necessitate a larger area of protected airspace to maintain safety and ensure proper separation between aircraft in a holding pattern.