FAA sets satellite navigation course
- By Paula Shaki Trimble
- Apr 11, 2001
The Federal Aviation Administration has targeted September 2003 as the first stop in its evolution to satellite navigation, but the agency's acquisition and research chief said Tuesday that it's time to reevaluate the business case for the system at the center of that effort.
The FAA plans to offer a safety-certified Wide Area Augmentation System in September 2003 that offers lateral and vertical guidance for landings when an aircraft is 400 feet above a runway and three-quarters of a mile away. WAAS uses a series of ground reference stations to verify and correct location information received from Global Positioning System satellites. WAAS also offers an integrity monitor that warns pilots if it predicts GPS data will be unreliable.
After the initial precision approach capability is in place, the FAA will add more reference stations to increase the coverage of WAAS over the continental United States to 100 percent. The third piece of the evolution is to decide if and when WAAS will offer what is known as a Category 1 precision approach, which provides guidance up to 250 feet above the runway and about a half mile away at some airports.
The plans are based on the technical specifications of a WAAS Integrity Performance Panel and the recommendations made in January by an independent review board moderated by the Institute for Defense Analyses in Alexandria, Va.
"I have a lot of my soul in this program," said Steven Zaidman, FAA associate administrator for research and acquisitions. "I'm encouraged that we have a date, a commitment."
However, Zaidman said he has asked the FAA to re-examine the business case for WAAS because of continued growth in costs due to delays and the slowed rate at which traditional ground-based navigation aids are being decommissioned.
"We have to justify there's value for the money," Zaidman said. "If there's not value for the money, we have to be upfront about that. I want to know my investment strategy is sound."
An enhanced WAAS system also may be unnecessary if the Local Area Augmentation System, which would provide more precise guidance at individual airports, is available before WAAS, industry sources have said.
While total program costs for WAAS have grown since its start in December 1994 because of a change of contractor and problems with the software that measures the integrity of the GPS signal, Zaidman said the cost of the contract with Raytheon Co. would remain steady at $494 million. Including costs of facilities and equipment as well as operations and maintenance has increased cost estimates for the total program through 2020 to more than $3 billion.
Zaidman said Raytheon is confident that it can deliver the lateral and vertical guidance capability as early as the second quarter of 2003, and the FAA is offering incentives to Raytheon to do so. He did not specify the amount of incentive because contract negotiations with Raytheon will not be complete until May or June.
Raytheon did not respond in time for this report.