How do I know which airspace requires what RNP value? More specifically, can I go from NY to London with just BRNAV providing I stay above the NAT HLA?
For completeness, Please refer to the following website:
Here are some extracts that allow to compare US and European requirements:
US Airspace Requirements
The current US RNP requirements are:
RNP-10 as described in FAA order 8400.12c
RNP-4 as described in FAA Order 8400.33
RNAV (RNP AR) approach authorization as defined in Advisory Circular (AC) 90-101a
Basic RNP capability is achieved through TSO-C146 compliant equipment when installed under AC 20-138().
RNP-10 and RNP-4 procedures are limited primarily to oceanic airspace.
RNAV (RNP AR) procedures are available in the US for domestic operations. These procedures require approval, hence the name: Authorization Required (AR), formally known as Special Aircraft & Aircrew Authorization Requirements (SAAAR) procedures.
European Airspace Requirements
There are two existing European RNP requirements:
Basic-RNAV (B-RNAV), equivalent to RNP-5 (reference FAA AC 90-45A, AC 20-130, AC 20-138, and AC 25-15)
Precision-RNAV (P-RNAV), equivalent to RNP-1.
These requirements are defined in European Aviation Safety Agency (EASA) Temporary Guidance Leaflet (TGL)-10, and FAA AC 90-96A. A statement is required in the Aircraft Flight Manual (AFM) or AFM Supplement (AFMS).
For European operations, a Letter of Authorization (LOA) for all RNP operations, is necessary, as the requirements differ from the FAA requirements.