FAA Extends WAAS Approach Decision Altitude to 200 Feet

The FAA is extending the lowest decision altitude capability of WAAS (wide area augmentation system)-enabled approaches from 250 feet above an airport's surface to 200 feet.

The change will allow an operational capability similar to a standard category I ILS (instrument landing system) where suitable airport conditions exist.

The FAA says the first procedures that allow operations down to 200 feet will be published in 2007.  The FAA currently has more than 300 vertical-guidance procedures, based on WAAS, and is expecting to publish 300 additional ones in 2006.

WAAS is a satellite-based navigation system that improves the accuracy, availability and integrity of GPS signals needed in these low-visibility flight operations.  When first commissioned in July 2003, WAAS was approved to provide vertical guidance down to 350 feet.  Localizer performance with vertical guidance procedures down to 250 feet was later developed to take advantage of the system's increased performance.  Over the past two years, WAAS has provided coverage to roughly 99 percent of the continental U.S. and has been available 99.87 percent of the time, according to the FAA.

There are approximately 3,000 WAAS-equipped aviation users operating in the national airspace system.  03-07-2006.

Click here to become a registered Flt Tech Online subscriber and receive headlines delivered to your e-mail each week

Click here to go back to the headlines