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President's PositionPresident's Position

ILS by satelliteILS by satellite

AOPA President Phil Boyer was among the first pilots to fly a GPS approach.

In July 2003 the FAA turned on the Wide Area Augmentation System (WAAS) designed to allow aircraft to make near-precision approaches, including vertical guidance like an instrument landing system, with GPS satellites aided by 25 ground reference stations. Despite airline resistance, for almost a decade your association has been engaged in this high-technology project that has required much staff time in the areas of advocacy, regulation, airport and approach design, and education. Throughout the lengthy process, AOPA was aware of the benefits that would accrue to general aviation instrument pilots if the new technology could be made to work to FAA standards. The $3 billion effort was fought by the airlines since they wanted the money spent on the Local Area Augmentation System (LAAS), giving them not just "near precision" approaches, but Category II and III (autoland) guidance primarily for air carrier airports. Six hundred large airports already are served by precision approaches. Yet, there are 5,400 public-use airports in the United States, with 15,509 runway ends. Today, only 4,686 of these have instrument approaches of any sort, leaving 11,000 runway ends available only in visual conditions.

Guess which airports get shortchanged? Often these are GA-only facilities in areas with year-round weather concerns and/or dangerous nearby terrain. The system AOPA fought hard to achieve basically allows WAAS approaches to thousands of additional runway ends, each approach flown like an ILS. Who wouldn't want the added safety of vertical guidance? And think of the cost benefit, considering the cost of a typical ILS installation to just one runway end can be more than a million dollars. Not many general aviation airports are eligible or can afford such an expense.

With last year's commissioning of WAAS, the government actually was ahead of industry by having an operational and certified system in place. At the time, manufacturers had no receivers to allow pilots to fly these approaches with vertical guidance. At the end of September certification was finally received for the first "sole means" WAAS receiver allowing vertical guidance, and primarily designed for general aviation aircraft: the Garmin GNS 480. The updated receiver was originally designed by UPS Aviation Technologies as the CNX80, and acquired last year when Garmin purchased UPSAT. AOPA had worked for many years alongside UPSAT advocating the benefits of WAAS to Congress and the FAA.

As I write this column, my personal CNX80 is back at Garmin being upgraded to allow use of the vertical guidance feature that will be displayed by the glideslope needle of my Cessna 172's existing course deviation indicator (CDI). Next year a WAAS upgrade will also be available for the popular GNS 430 and 530 models. For several years nonprecision approaches have been allowed using approach-approved GPS receivers, providing only lateral guidance to the runway. At many GA airports with minimal airport infrastructure, they offer the best instrument access. Minimums of 500 or 600 feet above the ground and 1 mile forward visibility exist with almost 2,000 of these renamed "LNAV" procedures, with a majority at air carrier airports. The newer LNAV/VNAV (lateral and vertical navigation) approaches exist at 700 airports, with more than 550 serving the airlines. These contain vertical guidance, but they usually have higher minimums than the lateral-only approaches. AOPA's home airport, Frederick Municipal in Maryland, is only one of six GA airports with the new LPV (which roughly translates to "localizer performance with vertical guidance") category. Runway 23 at Frederick has had a traditional ILS for years, with current straight-in minimums of 388 feet and one-and-one-half-mile forward visibility. The new LPV published approach shows minimums of 394 feet and the same forward visibility.

Preparing for a recent FAA International Safety Conference, we interviewed pilots on the airport ramp. None could identify what WAAS meant to their instrument flying. At the conference I implored the agency to not continue placing these approaches at airports already served by other procedures, but to place the new LPV approaches into GA airports for which they were intended. In this case I cited the need for owners to equip their aircraft, and the biggest motivator will be an LPV approach to an airport that has no ILS or one that has high minimums on the traditional nonprecision approach. Airport managers must be educated to better understand the applications and prepare to upgrade their airport for not only a GPS approach, but also now for an LPV approach. With strong FAA leadership, it is possible for the FAA to double the number of airports with near-precision approaches in the next four years because of WAAS.

FAA Administrator Marion Blakey has indicated her willingness to fly one of the first LPV approaches at AOPA's home airport with me in my 172. It will be a real thrill, and the culmination of at least phase one of our hard work on WAAS approaches. We'll be making a straight-in approach to Runway 23 with the expensive ILS on one CDI and the same vertical and horizontal guidance on the other with full knowledge the latter is being driven by the satellites alone.

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