WAAS Operational Facts
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View the operation of WAAS GPS equipment
The operation of WAAS GPS equipment requires:
- Your FAA Approved Aircraft Flight Manual Supplement.
- Your FAA Approved Aircraft Flight Manual.
- The equipment manufacturer’s operating/instruction manual.
- FAA Aeronautical Information Manual.
- WAAS NOTAMS.
- Appropriate approach charts.
- Appropriate training for the flight crew using WAAS procedures.
- AC 90-94 "Guidelines for Using GPS Equipment."
Advantages of using WAAS GPS
- Safety using Lower Minimums, LPV is typically 250 to 300 feet.
- Extremely Accurate GPS meets air navigation performance requirements for precision approaches, non-precision approaches, en route and terminal phases of flight.
- Better missed approaches.
- Opens up over 1,800 WAAS approaches with thousands more to come.
- Affords better weather minimums at many of the airports (some are LPV200 as low as 200 feet).
- Removes the GPS RAIM FDE checking requirement.
- Removes the Low Temperature Approach requirement.
- Uses two GEO satellites for redundancy.
- Approved in 48 states, Alaska and Canada. (Mexico is working on similar approvals.)
- Lowers the FAA flight inspection costs.
- May increase airspace capacity under the FAA’s NextGen
program.
The FAA has announced the decommissioning of some existing Navaids including NDBs, Cat1 ILS, VORs and Markers. Watch your charts to see these changes.
Benefits of WAAS
- Flexibility.
- Better Weather Minimums.
- Creates more alternate airport opportunities.
- Gives a corporate/business traveler closer proximity to desired locations.
- Allows the flight crew to fly precision approaches as low as
200 feet, typically below 300 feet.
Duncan Aviation wishes to acknowledge the FAA, Raytheon, Mitre Corp., Stanford University and the avionics manufacturers for this information.
WAAS Approach Locations
WAAS approach locations as of February 2008 (visit faa.gov for a more recent update). Total of 1,084 WAAS LPV approaches. Total of 12 LPV 200 approaches. There are over 1,500 ILS approaches available.
| Approaches by State | #LPV | #LPV <260 ft | #ILS |
|---|---|---|---|
| Alaska | 16 |
12 |
30 |
| Alabama | 25 |
11 |
26 |
| Arkansas | 20 |
13 |
25 |
| Arizona | 12 |
4 |
18 |
| California | 35 |
12 |
76 |
| Colorado | 8 |
5 |
36 |
| Connecticut | 7 |
0 |
7 |
| District of Columbia | 3 |
1 |
10 |
| Delaware | 4 |
0 |
3 |
| Florida | 80 |
19 |
71 |
| Georgia | 58 |
21 |
53 |
| Iowa | 27 |
21 |
22 |
| Idaho | 9 |
8 |
9 |
| Illinois | 36 |
12 |
55 |
| Indiana | 32 |
12 |
33 |
| Kansas | 32 |
26 |
24 |
| Kentucky | 15 |
4 |
21 |
| Louisiana | 19 |
4 |
23 |
| Massachusetts | 8 |
1 |
23 |
| Maryland | 6 |
1 |
16 |
| Maine | 8 |
4 |
13 |
| Michigan | 19 |
4 |
50 |
| Minnesota | 24 |
15 |
39 |
| Missouri | 42 |
14 |
33 |
| Mississippi | 26 |
11 |
24 |
| Montana | 7 |
4 |
11 |
| North Carolina | 29 |
9 |
51 |
| North Dakota | 15 |
11 |
14 |
| Nebraska | 54 |
32 |
18 |
| New Hampshire | 5 |
2 |
19 |
| New Jersey | 13 |
4 |
16 |
| New Mexico | 10 |
8 |
17 |
| Nevada | 4 |
1 |
10 |
| New York | 28 |
14 |
52 |
| Ohio | 30 |
10 |
45 |
| Oklahoma | 13 |
5 |
30 |
| Oregon | 14 |
3 |
18 |
| Pennsylvania | 36 |
12 |
41 |
| Rhode Island | 3 |
1 |
4 |
| South Carolina | 19 |
9 |
22 |
| South Dakota | 15 |
9 |
12 |
| Tennessee | 9 |
7 |
28 |
| Texas | 82 |
54 |
104 |
| Utah | 4 |
0 |
13 |
| Virginia | 20 |
6 |
25 |
| Vermont | 1 |
0 |
3 |
| Washington | 22 |
3 |
31 |
| Wisconsin | 32 |
5 |
27 |
| West Virginia | 1 |
0 |
12 |
| Wyoming | 12 |
8 |
9 |
North America WAAS Coverage
 |
LPV200 Service Contour (solid yellow line) LPV Service Contour (solid red line) LNAV/VNAV Service Contour (dashed black line, includes LPV) Color Scale is Vertical Protection Level (VPL) 08-December-2007 13:27:10 GMT (WJH FAA Tech. Cntr., NJ USA) |
As indicated by the FAA graphic above, nearly all of North America has GPS LPV accuracy.
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