William Sussman

The proposed rule includes guidance from AIM 1-1-19 g. and 1-1-20 c. 7., stating "When a planned alternate is required, that alternate cannot be predicated on GPS in any way." The proposed rule allows, however, that "General aviation aircraft using WAAS equipment under IFR do not require an alternate means of navigation, due to the improved reliability of WAAS." However, many WAAS-equipped aircraft (such as G1000-equipped single-engine Cessnas) have a limitation that states the following: "1. The airplane must be equipped with an approved and operational alternate means of navigation appropriate to the route being flown (NAV receiver, DME or ADF). "2. For flight planning purposes, if an alternate airport is required, it must have an approved instrument approach procedure, other then GPS or RNAV, that is anticipated to be operational and available at the estimated time of arrival. All equipment required for this procedure must be installed and operational." The proposed rule states "The FAA is planning a gradual discontinuance (removal from service) of VOR facilities in CONUS to a minimum operational network (MON).The MON would enable aircraft anywhere in the CONUS to proceed safely to a destination with a GPS-independent approach within 100 nm." If an alternate airport for destination is required, the MON may result in the only legal alternate being up to 100 nm away for all non-WAAS and even most WAAS-equipped aircraft. This will effectively reduce aircraft range and result in the need for a fuel stop on longer flights that currently could be conducted in one leg. Please consider the economic impact of this as you decide which legacy NAVAIDs to include in the MON.