A publication of the National Air Traffic Controllers Association
Issue link: http://natca.uberflip.com/i/1016075
possible to add advanced RNP minimums to an RNP AR chart in the manner of Cat I, II, and II I ILS being on a single chart. This lead to discussio n of what would be in the PBN box (seems like it could have two NavSpecs), what possible RNP values could be used for advance RNP (ICAO is heading toward allowing only two values, 1 NM or 0.3 NM), a nd which OPSPEC would pertain. None of this really address ed the harmonization of the procedure design criteria, but it is all pertinent and will have to be addressed in a recommendation. There is major support for allowing both AR and advanced RNP (as well as GLS and LPV) mins on the same chart from the operator s. During this discussion we realized that there was a misunderstanding within the WG regarding the application of 2xRNP OEA to IAPs requiring advanced RNP. The intent of the recommendation to FAA had been to apply the 2xRNP OEA to all segments of the a pproach includi ng the final segment. Some members had not taken the recommendation to apply in the final segment. Once the discussion was finished the group consensus once again was that the O EA must apply to all segments. Because of the misunderstanding within our own group, the Nav WG will need to follow up with an amendment to the recommendation and send to t he SG for transmittal to AVS - 1. Mike Cramer and Barry Miller (will take this action. Another side issue that arose was whether the Nav WG needs a more detailed (lower level) "roadmap" than the PBN Strategy to guide our efforts. The preceding discussion is an example of needing such guidance. There was discussion of requesting the PARC SG to break down the PBN Strategy into a more detailed roadmap f or PARC in s upport of the strategy. Open issue. Mike then pulled the group back to the original topic, which was harmonizing the criteria for the OCS final to missed approach transition. Mike and Gary P. worked together walking through a very detailed com parison of ICAO and AR methods which was provided by Bill Fernandez. It is an excellent comparison of the two methods and is on the Nav WG website in the meeting folder. Gary P then presented his ideas for how the methods could be made the same, which w ould also finally solve the 250' H AT problem for RNP AR as well. A review of two cases (RNO RWY 16R and SAN RWY 27) will be done to confirm that the proposed methods could in f act lower the RNP AR minimums. The Nav WG consensus agreed with Gary's proposed method, so Mike asked that Gary prepare a detailed recommendation draft by the end of September if possible for final revi ew and approval in the Q4 F2F. Gary agreed, and Mike asked Gary McMullin (Southwest) and Ron Renk (United) to help with an early revie w and comment on the draft before it goes out to the whole group for review. Mike will also review. 2. TF Overlay for RF (Work Session): Mike opened the discussion by noting that the group needed to reach consensus on several factors; particularly the desig n variables that need to be considered, the criteria for successful overlay, technical issues that could affect the designs, and atmospheric conditions that could r esult in failure of the designs of the radius, turn extend and groundspeed.