A publication of the National Air Traffic Controllers Association
Issue link: http://natca.uberflip.com/i/961329
volunteers were Mike Cramer (MITRE), Al Herndon (MITRE), Larry Hills (FDX), Brian Swain (DAL), Ron Renk (UAL), Andrew Benich (Envoy), Chris Shehi, Barry Miller (FAA AIR) and Gang Feng. A ‐ RNP Issues Work Session Mike summarized the three A ‐ RNP issues that had been ag reed as high priority for 2018. Each was discussed individually. OEA Harmonization The harmonization of the OEAs was discussed first, and as review, Mike asked Barry to walk through his white paper on justification for moving to 2xRNP for the OEA in A ‐ RN P to match RNP AR. The main basis for proposing the same OEA for A ‐ RNP rests on the fact that both A ‐ RNP and RNP AR have identical hazard classifications and required design assurance for RNP 0.3 or greater. The more stringent requirements for RNP AR come into play when the RNP value for the operations is less than 0.3. After this second review of the paper, the group agreed that they thought the paper provided sufficient justification for a recommendation that the A ‐ RNP OEA be reduced to 2xRNP from 3xRNP. Mike was asked to draft the recommendation and forward it to the SG for review and approval. Maximum Design Bank = 25 Degrees Discussion of raising the minimum design bank angle for A ‐ RNP to 25 degrees involved a review of the MITRE aircraft / avionics c apability table. This table includes for each system the maximum available command bank angle which can be used. Some systems have a maximum of 25 degrees, but many have 27 and up to 30. It was noted that if we allow design up to 25 to set the minimum RF r adius in a procedure, there is no margin in some systems for remaining on the RF path except for the margin built in by designing to the maximum wind speed / direction expected. This is probably sufficient, however the group felt that we should perform ana lysis 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. Multiple Intermediate Segments: Multiple intermediate segment s (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 a nd 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