Newsmakers 2009: FAA OKs field approvals for Waas LPV upgrades

 - December 28, 2009, 10:59 AM

Universal Avionics spent much of the last year working with FAA officials trying to come up with a way to upgrade the customers’ flight management systems for Waas LPV approach capability under a basic field approval rather than having to submit to the cumbersome supplemental type certification process. The result of that effort was an agreement struck in September that clears a path for more than 1,000 business jet operators to take advantage of the new guidance.

Universal Avionics was the first FMS maker to obtain TSO C146b approval for Waas-capable flight management systems, but the FAA requirement that the Waas LPV upgrade be done under an STC that often involved the submittal of “issue papers” for each airplane meant few operators could take advantage of the lower Rnav approach minimums. At last count the FAA had created 1,884 Rnav procedures with Waas LPV (lateral precision with vertical guidance) minimums, which are similar to Category I ILS minimums yet don’t require the installation of airport-specific ground equipment. The FAA is bringing the satnav capability to airports around the U.S. as part of a plan to begin phasing out many ILS installations and provide precision approach capability at thousands of airports that until now relied on VOR, NDB and basic Rnav approaches.

Upgrading for Waas LPV using the Form 337 field approval process will allow many operators to have the work completed while their airplane is in the shop for scheduled maintenance. To meet the eligibility requirements set down by the FAA, airplanes are required to be registered in the U.S. and the Universal FMS installation must already be approved for 3-D coupled “pseudo-ILS” procedures. The field approvals can be done only on an existing FMS installation, meaning operators cannot switch from another manufacturer’s FMS to a Universal FMS or add a second Universal FMS and do the basic field approval.
Stevens Aviation in Greenville, S.C., was the first to complete the Waas LPV upgrade under the new rules, signing off on an FMS modification in a customer Learjet 31 on September 9. Universal has spent the last few months talking with dealers and customers about how they too can take advantage of the relaxed FAA guidance. Other FMS makers are watching the development closely, but so far none has struck a similar agreement with the FAA.