What capability should an aircraft operating to RNP1 possess?

The correct capability for an aircraft operating to RNP1 is to compute an estimate of its position error. RNP, or Required Navigation Performance, establishes a standard for the accuracy of navigation systems used by aircraft. At the RNP1 level, an aircraft must have the ability to navigate with a certain degree of accuracy and predict its position performance based on available data.

For RNP1, it is not necessary for the aircraft to compute the exact value of its position error, as this would require a level of precision and detail that exceeds the standard set for RNP1 operations. Instead, understanding the estimated position error provides sufficient information to maintain safe and accurate navigation within the required performance limits. This estimation allows pilots and navigation systems to monitor navigation performance adequately without needing to determine an exact error value, which can be complex and resource-intensive.

Therefore, the focus is on estimating the position error to ensure safe navigation and operational compliance within the RNP1 framework, rather than correcting or computing an exact position error, which is unnecessary for this level of performance.