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20-138D - Airworthiness Approval of Positioning and Navigation Systems (Including Change 2)

Date Issued
March 28, 2014
Responsible Office
AIR-130,  Aviation Safety - Aircraft Certification Service, Aircraft Engineering Division

This revision adds minor clarifications and new guidance material based on issues and questions since revision ‘C’ was published. There are several new changes such as: equipment capability versus installed limitations; clarifying database configuration versus equipment capability; adding step-down fixes to navigation databases; a new appendix for demonstrating radius to fix (RF) leg capability; and, including required navigation performance (RNP) prediction guidance for RNP authorization required approach (RNP AR APCH).