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airports and when the Height Above Touchdown (HAT) approaches 250', so it was decided to leave that requirement as is. Further discussion of possibly allowing times shorter than 15 seconds as standard was decided against primarily because in the limited times that might be advantageous the 15 seconds could be waived by AFS after review. In addition, Barry Miller (FAA AIR) pointed out that ICAO was moving toward the 15 second standard, and Jeff Kerr (FAA AFS) pointed out that in the draft Advisory Circular (AC) they had adopted the 15 in anticipation of the Nav WG recommendation. The final version of the recommendation was agreed upon, recommending simply that a standard minimum of 15 seconds prior to DA for the FROP be applied, and the 50- second time removed from criteria 2. RNP AR Departures - As a follow-on to the previous briefing, Barry Miller briefed the group on the work being done on RNP departures at ICAO. His briefing is posted to the Nav WG PARC site in the meeting folder. 3. FAA Briefing on AC90-101A Update Progress - Jeff Kerr (AFS-470) had previously asked for a time on the agenda to brief the group on what changes are upcoming in AC90-101A. Greg Spann gave the briefing which will be included on the website as part of the meeting records. The general reaction was positive from the group. They also shared a draft RNP AR compliance guide, which will be being replaced by online guidance soon (this will also be available on the PARC website for the Nav WG). Jeff asked for volunteers to join in a working review of the AC to help FAA refine the document and better coordinate it with industry prior to the public comment period. The group of 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. 4. A-RNP Issues Work Session - Mike summarized the three A-RNP issues that had been agreed as high priority for 2018. Each was discussed individually. a. 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-RNP 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. b. 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 capability 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 radius 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 /

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