In a major step toward
reducing reliance on a ground-based navigation infrastructure,
the FAA has announced that Wide Area Augmentation System
(WAAS) use is being extended from the current 250 feet above an
airport’s surface to 200 feet for vertical instrument
approaches.
WAAS will be available to all users equipped with the
appropriate avionics. This change will enable WAAS vertical
guidance procedures to achieve an operational capability similar to
an instrument landing system, where suitable airport conditions
exist. Those airports that do not have the appropriate conditions
may require additional infrastructure and airspace upgrades.
WAAS-equipped commercial operators will gain access to Category
I equivalent approach services at qualifying airports where there
are no instrument landing systems. This will result in improved
safety, including enhanced approach and landing operations in
marginal weather.
“This is a significant milestone, moving us closer to our
ultimate goal of a satellite-based airspace system,” said FAA
Administrator Marion C. Blakey.
The FAA plans to expand the application of these lower minima
approaches beyond current instrument landing system airports. 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 and is expecting to publish 300 additional ones
in 2006.
Originally 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 increased performance provided by WAAS. Over the past two
years, WAAS has provided coverage to roughly 99 percent of the
continental United States and has been available 99.87 percent of
the time. WAAS continually exceeds performance expectations.
WAAS is a satellite-based navigation system designed to improve
the accuracy, availability and integrity of signals from Global
Positioning System (GPS) satellites.
Although WAAS was designed for aviation users, it supports a
wide variety of non-aviation uses including agriculture, surveying,
recreation, and surface transportation, just to name a few. The
WAAS signal has been available for non-safety applications since
August 2000, and numerous manufacturers have developed WAAS-enabled
GPS receivers for the consumer market. Today, there are millions of
non-aviation WAAS-enabled GPS receivers in use. There are
approximately 3,000 WAAS-equipped aviation users operating in the
national airspace system.