What is the maximum altitude for RNAV aircraft operating on random routes that requires radar separation?

For RNAV aircraft operating on random routes that require radar separation, the maximum altitude is Flight Level 450. This altitude corresponds to the operational capabilities of advanced RNAV systems, allowing for efficient routing in the airspace. Above this level, the complexity of air traffic management increases and other factors come into play, including diminished radar coverage and the need for more stringent separation standards between aircraft.

Flight Level 450 is significant as it represents a boundary for RNAV operations in certain airspace configurations. Radar separation is particularly important in this envelope to maintain safety and efficiency in operations, especially considering the potential for high-density traffic and the altitude ranges at which many aircraft operate.

Lower altitudes such as 10,000 feet would typically relate to different traffic management protocols, while Flight Level 300 and lower Flight Level restrictions do not encompass the more expansive random routing that RNAV allows at higher levels. As such, Flight Level 450 is the correct designation for this operational context.