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direction expected. This is probably sufficient, however the group felt that we should perform analysis to support this assertion. Mike agreed to take the action to work with analysts at MITRE to do this analysis, Wes Combs volunteered to help. There will be no recommendation on this until after the analysis is complete and it supports the limit change. It should be noted that RNP AR already allows up to 25, and some systems that qualify for RNP AR are the same ones, which are limited to 25 degrees maximum control bank for path keeping. c. Multiple Intermediate Segments: Multiple intermediate segments (and fixes) are a principle part of RNP AR designs in places with multiple runways and approaches (e.g., KDEN). Early in the implementation of RNP AR a PARC working group was assembled to look at the issue of chart clutter associated with multiple IFs and the profile view of the procedure. We reviewed that recommendations that were made there and at the ACF in this meeting to understand if there were any differences between RNP AR and A-RNP that would invalidate use of multiple IFs for A-RNP since it would be advantageous to replace RNP AR procedures with RFs and minima 0.3 or above with A-RNP procedures to improve participation. Review of the preceding work for AR and discussion found no reasons that the multiple IFs should not be allowed for A-RNP as well as for RNP AR. Mike has the action to draft a recommendation for review in our next telcon. Recommendation Problem Statement Current criteria does not allow the use of multiple intermediate fixes (segments) for procedures other than RNP AR, such as A-RNP instrument approach procedures see Order 8260.19H paragraph 8-2-2.c. Multiple fixes (segments) are allowed in RNP AR procedures per Order 8260-58A based in part on the PARC RNP Charting WG recommendation (12 March 2010) which was responding to ACF 09-02- 220. The PARC work was taken to the Aeronautical Charting Forum at ACF 10-02. It specifically recommended limiting multiple IFs to RNP AR but raised the question of allowing them for other procedure types, recommending that the issue should be revisited after more experience had been gained. While discussing the possibility of replacing some RNP AR procedures where A-RNP should suffice, the Navigation WG realized that this would be an issue. Using A-RNP instead of RNP AR for procedures only needing the RF and RNP values down to 0.3 NM to expand participation to more aircraft lead the WG to an examination of the Denver RNP AR procedures that meet these criteria. The Denver procedures, however, make extensive use of multiple intermediate fixes and segments for implementation, which is not allowed except for RNP AR. In 2017, the WG added this issue to the work plan for 2018. After review of the original ACF material and subsequent discussion the WG could find no differences between RNP AR and A-RNP operations that would drive a restriction on use of multiple IFs in A-RNP procedures. Given that current criteria don't mention use of multiple IFs outside of RNP AR, and that operations and equipment are very similar between AR and ARNP, the WG concluded that multiple IFs for A-RNP is both feasible and practical to gain the benefit of expanding fleet use through A-RNP in many cases. The Navigation WG recommends that the FAA revise criteria to allow the use of multiple intermediate fixes (segments) in IAPs requiring the A-RNP NavSpec in the same manner as implemented for RNP AR (down to RNP 0.3).

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