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showed that either method provides sufficient margin for staying on the path, using them both together is not necessary. All agreed that for future, this is covered by DO-236C which requires all RNP RNAV capable aircraft control to provide bank up to 30 degrees for path keeping. Barry Miller pointed out that the demonstrated RF capability criteria in AC20-138 will eliminate fleet types with LNAV functionality not suitable for using designs up to 25 degrees. Mike is to edit the draft recommendation to state that this should be limited to AR and A-RNP qualified aircraft and to address the TF only transitions and bank criteria. Garmin (Clay Barber) had asked that a statement be added to point out what airframe types might be excluded as part of the recommendation. Gary Petty suggested that some example sites where this change would have allowed a more beneficial procedure might help the recommendation; Mike will research. Mike has the action to revise the draft recommendation for the May 30 telecon. 4. Intermediate Segment Length: Mike had circulated the draft recommendation prior to the meeting, receiving one response that disagreed with the additive ROC proposed when a step-down fix is included in the segment. Discussion centered on the possibility that by updating the criteria in this way, we might be invalidating existing procedures. Gary P. agreed to analyze examples to determine if this is a problem or not. Gary McMullin from SWA proposed KBOI and KABQ as examples for analysis. Gary Petty (AFS-420) agreed that could run the numbers on these two and report back to the WG by next telecon. 5. Future Meetings: The 2018 quarterly meetings have been scheduled and invitations sent via Outlook calendar. The F2F and next virtual meeting has been added to the website calendar. Virtual Meeting – May 30, 2018, 1 p.m. EDT 2018 Q3 F2F – August 1 & 2, Seattle hosted by Boeing 2018 Q4 F2F – November 7 & 8, Atlanta hosted by Delta 6. New Business - There were three items brought to the meeting for discussion. a. Gary McMullin briefed the group regarding inconsistency between STAR termination altitudes and the first altitude on an approach in some instances. While the STAR should not terminate at an altitude below the first approach constraint altitude, there are occasions where this has happened. In these cases, the approach cannot be loaded into the FMC. He cited examples in KMSP which should be reviewed. b. Gary McMullin also brought up intermediate segment gradient criteria which has been reduced from the final segment. He would like to see it returned to previous version of .3C where it could be matched to the final segment gradient for better VNAV performance. c. Mike Cramer (MITRE) asked Gary Petty (AFS-420) and Nick Pettiet (AFS-420) if they could walk the WG through a comparison of the methods used to connect the final OCS to the missed approach OCS in RNP AR and LNAV/VNAV. The difference can lead (often) to lower minimums for LNAV/VNAV than are attainable with AR. This has been added as a high priority for 2018. The walkthrough was informative (on short notice, thanks Gary and Nick) and gave the WG a good overview. Gary has a method in mind to harmonize the two and will continue his research with a status update May 30 telecon.

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