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more safety benefits such as improved situational awareness (SA), near real-time weather information, and additional voice communications. 

2. ADS-B services have been deployed to all 24 modernized enroute ARTCCs and the largest terminal radar approach control facilities in the NAS. In 2020, ADS-B will be mandatory for all aircraft in almost all NAS controlled airspace. [Figure 5-8] 

3. Satellite-based technologies, including the Wide Area Augmentation System (WAAS), are improving access to runways at both large and small airports. [Figure 5-9] Directions and maps have been published for more than 500 precision-like approaches enabled by WAAS. Localizer performance with vertical guidance (LPV) procedures improves access to airports in lower visibility conditions and where obstacles are present. These procedures are particularly valuable for smaller airports used by general aviation. There are now oer 2,300 LPV procedures available at runways where no instrument landing system (ILS) is present. 

4. The Ground-Based Augmentation System (GBAS) has been approved for Category I operations and the first satellite-based system has been approved for this category of precision approach which enables instrument-based operations down to 200 feet above the surface even during reduced visibility. [Figure 5-10] GBAS was installed at Houston, Texas and Newark, New Jersey airport in 2009. 

5. Multilateration, a ground-based surveillance technology, is being implemented to help improve runway access. The FAA installed and is now using wide area multilateration (WAM) systems to control air traffic in Juneau, Alaska, and at four airports in Colorado. This allows air traffic to be safely separated by five miles whereas before each aircraft had to clear the airspace around the airport before the next could enter. 

6. New runways at Chicago O’Hare, Washington Dulles, and Seattle-Tacoma Airports opened in November of 2008, which are now beginning to have a reduction in delays. 

