A publication of the National Air Traffic Controllers Association
Issue link: http://natca.uberflip.com/i/806148
Pilot Controller Procedures & Systems Integration (PCPSI) Our next meeting is scheduled for April 10, 2017. PARC NAV WG Vertical angle on the FAF During RNP to ILS testing o f the shallow segment designs it was found that the data suppliers were by default coding the final segment angle on the FAF, negating the shallow segment (which is around two degrees). Review of ARINC 424 standards and the processes with the suppliers rev ealed that the blanket extension of the final segment angle into the intermediate segment, while necessary in the rare instances where there was a step - down in the intermediate, was being applied to all precision approaches. The standard allows no angle on the FAF as an option, which should really be applied in most cases. A white paper has been written and will be taken to the ARINC 424 meeting in March for review. During the March ARINC 424 meeting, the presentation helped the group understand the issues created by the vertical angle being routinely coded on the xLS FAF (the glideslope angle which is also coded on the MAP). Since everyone in this group had accepted the existing text in ARINC 424 (21 is current), it fell upon the data providers (Jeppesen, LIDO, NAVDATA) to explain that they routinely code the vertical angle on the FAF (contrary to the 424 exception) to simplify their processes. Both Jeppesen and LIDO agreed to comply and LIDO has already taken action to make that happen since there was some work with them behind the scenes some weeks ago, on this issue. Jeppesen is looking into how they will change their processes and a notification to their customers will precede the actual change, in which ARINC 4224 will receive a copy of that notice. The overall process change should not be a big deal though from an operator's perspective, because all of the FMSs will do what they are told by the NDB anyway. It really is just a case of ensuring the NDB is correct. One thing to note is that some procedures will keep the vertical angle on the FAF for those procedures that require it (i.e., ALT1 and ALT2 are different because of some obstruction issues between the FACF and FAF). All other procedures should have the ver tical angle on the FAF removed. Addition ally, a question was sent to the FAA and the explained they are providing the state data to the providers in accordance with ARINC 424 - 18, an older version that has slightly different (but an important difference) language. FAA personnel agreed that they s hould be providing state data to the data houses IAW the current ARINC version (21) and will change their processes internally to comply with ARINC 424 - 21 thus making the task somewhat easier on the data houses. ARINC 424 cannot speak to what the other sta tes are doing, but their committee and specifically the major data houses will check with their sources. Regardless, it is a process, which can be contro lled by the data folks anyway. Our next meeting is scheduled fo r May 9 - 10 in Denver . Established on D eparture Operations (EDO) The last EDO HITLS were conducted during the week of January 30th and various scenarios have been run over the last month or s o using Fast - Time Simulations. We will receive the draft report from the Tech Center on March 31, 2017 with comments due back by April 10, 2017 and the final report will be released on April 21, 2017. Once the