What do a Cessna 172 and a Boeing 747 have in common? Not much, other than they both have wings and fly. And that's why AOPA is urging the FAA not to apply commercial airport standards to small general aviation airports that want to offer WAAS (Wide Area Augmentation System) instrument approaches.
"While the FAA is updating its Airport Design Handbook, the agency needs to find a way to tailor its design criteria for GA airports to the type of aircraft, which have smaller wingspans and slower approach and landing speeds, that operate there," said Andy Cebula, AOPA executive vice president of government affairs. "Right now, a 2,900-foot runway would have to meet some of the same criteria as a commercial runway to offer a precision approach like WAAS, and that's just not feasible."
Satellite-based WAAS has the ability to offer virtually the same approach minima as an ILS - 200 feet and one-half-mile visibility - without all of the ground-based navigation equipment and cost. The FAA is rolling WAAS out all across the country, but it is difficult for small GA airports to upgrade.
Currently, in order to offer WAAS, an airport must have much of the ground infrastructure, like approach lights, precision runway markings, and a parallel taxiway, that an ILS requires.
As expensive as those changes would be, the most expensive investment would be purchasing tens of acres of land at the end of a runway to clear potential obstacles. A safe approach to the runway is needed, but AOPA says it should be sized appropriately.
"Many small GA airports that would benefit from WAAS can't afford to create the required huge runway clear zones designed for commercial airports," Cebula said. "And that is just one example of a design standard that can be tailored to the type of aircraft that fly at these kinds of airports.
"The success of WAAS and satellite navigation depends largely on the FAA's ability to better match up design criteria with the aircraft at a particular airport."
June 7, 2006