In RNP airspace, when are pilots allowed to fly?

In RNP (Required Navigation Performance) airspace, pilots are allowed to operate when they are using civil standards for certification. This means that the aircraft must meet specific performance and operational requirements established for RNP operations. These standards ensure that the aircraft is capable of navigating accurately and reliably within RNP airspace, which may include precision approach procedures and various routing capabilities.

Compliance with these civil certification standards is essential for ensuring safety and efficiency in flight operations, particularly in regions where navigation performance is critical for maintaining the spacing and separation of aircraft. Achieving and maintaining the necessary equipment, training, and procedural standards is crucial for a successful operation within RNP airspace.

Other options relate to operational practices or conditions that, while important in general aviation, do not address the specific requirements for RNP airspace operations directly.