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dispersion should be reduced as the aircraft will be on the VI leg a shorter distance. A question was raised as to whether wind was a factor. This has not been the case in all the tracks according to Will Bachman (MITRE), as he has looked at one week of data, and the tracks are still on both sides, even when crosswind should be causing drift to one side. Alternative coding was discussed as an option with use of a course to intercept (CI) leg. While this would assist on drift issue, it would still exhibit some issues depending on when LNAV is engaged but will be reduced. The problem with alternative coding is that the procedure would need to be coded as a VI or vector to altitude (VA) leg and then the database coder would have to modify to a CI or course to altitude (CA) leg. This would depend on the manufacturer and the aircraft. It was asked if changing the wording on the SID to "track" rather than "heading" would solve the issues. With this wording, the database coder would change VI to a CI or CA, which is not what we want, nor would it solve the issues. Potential solutions would be to shorten the VI leg to standard of 1 NM or design VA-direct to fix (DF) leg. Based on discussions with the Cleveland/Detroit Metroplex team, they are moving forward designing RNAV SIDS using VA-DF legs. • New Business: Modernizing ATM with RNP – Shelia Conway (Boeing) gave a presentation on RNP-established (RPNe), which has been approved at five sites internationally with many more in process. For ICAO, ILS, and RNP with runway separation are based on RNP value. A recent rule change allows reduced separation when on APV with RNP, if performance and operational error mitigations are demonstrated. This rule change was based on a 2011 PARC NAV WG study and was incorporated into ICAO PANS ATM and SOIR rules in November 2018. LHR was presented as a site where the new rule is currently being implemented. Calgary implementation was presented with the change they made to create divergence between RNPs to parallel runways to recognize conformance. DEN implementation of EoR was shown in operational use with Nick Tallman explaining the development. Gary McMullin (SWA) and other industry partners mentioned concern in the rollout of the EoR Incorrect Flight Procedure Selection. They would like to open a task to reevaluate these criteria. Conway has the task to initiate this request. Mark Bradley (DAL) has a request from SWA to review the EoR/RNP incorrect flight procedure selection, and Cramer will coordinate the request with him. Our next meeting is scheduled for April 30-May 2 in Denver. PBN NIWG There is nothing new to report at this time, regarding the PBN NIWG.

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• SAFETY AND TECHNOLOGY DEPARTMENT