NATCA Bookshelf

WAKE TURBULENCE John Murdock (PHL) is the Article 114 Representative to the Wake Turbulence Office for NATCA. His report is below: Initial meetings were held and completed at A90 and D10 for CWT implementation. Training has or is about to start at both facilities and IOC will be completed for both facilities by the end of May. Currently, no other facilities are scheduled to implement CWT. A waterfall schedule for current facilities to upgrade from RECAT 1.5 and 2.0 to CWT is being developed. There are many issues with the assignment of wake turbulence categories in RECAT 2.0. The Agency designates some, not all, new aircraft in RECAT 2.0, a non-pairwise heavy category (category G). The Agency will not assign a pairwise category until they are able to evaluate the wake turbulence produced by the aircraft, and until they have collected enough LIDAR data. Essentially, the LIDAR system is at one airport that can collect the data for all the aircraft. Until an aircraft flies into that airport, no specific amount of times, the category of the aircraft in RECAT 2.0 will not change. It could take years to collect the amount of data the Agency wants, to categorize the aircraft. The 7110.65 and RECAT 1.5 both do not have a non-pairwise heavy category, so these same aircraft are categorized via legacy procedures. For example, the B78X aircraft is a non-pairwise heavy in RECAT 2.0 (category G); in the 7100.65 it is a heavy and RECAT 1.5 it is an upper heavy. This is significant because controllers in RECAT 2.0 facilities apply significantly more separation with this aircraft compared to facilities that use 7110.65 and RECAT 1.5 rules. If a B744 is following the B78X on approach in a RECAT 2.0 facility, the separation standard for wake turbulence is seven miles in-trail. The same combination of aircraft at a RECAT 1.5 facility is three miles in-trail. Also, the RECAT 2.0 controller must provide seven miles in front of the B78X; and if the B78X is following a C172, the B78X must be seven miles in-trail of the C172. CWT addressed this significant disparity in separation rules. If RECAT 2.0 facilities are upgraded to CWT, they will see significant relief from the issues associated with the non-pairwise heavies in RECAT 2.0. There are other issues being addressed with the updating of the aircraft databases in the facilities. It has been over two years since the last update and there are aircraft that are the wrong category in the databases. There is a fight at FAA HQ on who can actually categorize the aircraft and when. The agency has resorted to using GENOTs to correct the errors. Some GENOTs are approaching a year old and should not be the solution to the inability of the Agency to update the aircraft databases. April 15-21 Update

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• SAFETY AND TECHNOLOGY DEPARTMENT