Orbit Reference Values (with respect to an epoch of 1 July 1990 00:00:00)
| Satellite ID | Argument of Latitude | Geographic Longitude of Ascending Node | Right Ascension of Ascending Node |
| A1 | 280.7 | 358.6, 178.6 | 317.0 |
| A2 | 310.3 | 13.4, 193.4 | 317.0 |
| A3 | 60.0 | 248.2, 68.3 | 317.0 |
| A4 | 173.4 | 304.9, 125.0 | 317.0 |
| B1 | 339.7 | 88.1, 268.1 | 17.0 |
| B2 | 81.9 | 319.2, 139.2 | 17.0 |
| B3 | 115.0 | 335.7, 155.8 | 17.0 |
| B4 | 213.9 | 25.2, 205.2 | 17.0 |
| C1 | 16.0 | 346.2, 166.3 | 77.0 |
| C2 | 138.7 | 47.6, 227.6 | 77.0 |
| C3 | 244.9 | 100.7, 280.7 | 77.0 |
| C4 | 273.5 | 115.0, 295.0 | 77.0 |
| D1 | 42.1 | 59.3, 239.3 | 137.0 |
| D2 | 70.7 | 73.6, 253.6 | 137.0 |
| D3 | 176.8 | 126.6, 306.7 | 137.0 |
| D4 | 299.6 | 188.0, 8.0 | 137.0 |
| E1 | 101.7 | 149.1, 329.1 | 197.0 |
| E2 | 200.5 | 198.5, 18.5 | 197.0 |
| E3 | 233.7 | 215.1, 35.1 | 197.0 |
| E4 | 335.9 | 266.2, 86.2 | 197.0 |
| F1 | 142.2 | 229.3, 49.4 | 257.0 |
| F2 | 255.6 | 286.0, 106.0 | 257.0 |
| F3 | 5.3 | 160.9, 340.9 | 257.0 |
| F4 | 34.5 | 175.6, 355.7 | 257.0 |
Source: NATO. 1991. NATO Standardization Agreement Navstar Global Positioning System: System Characteristics. 1 February 1991.
The argument of latitude is the geodetic latitude of the satellite at the epoch. In this table the latitude is expressed as an angle between zero and 360 degrees, starting at the equator and going around the earth through both poles, returning to the equator at 360 degrees.
The geographic longitude of the ascending node is the geodetic longitude where the satellite is at the reference epoch. Since the longitude of each satellite is given independently of latitude, it is given for both sides of the earth (i.e. longitude and longitude + 180 degrees).
The right ascension of the ascending node is the geodetic longitude at which each orbit plane intersects the equator at the epoch.
Nominal Orbit Tolerances
| Parameter | Value | Offset | Accuracy | Accuracy(10 year life) |
| Eccentricity | 0 | 0 | less than 0.020 | less than 0.020 |
| Inclination | 55 deg. | 0 | +/- 0 1 | +/- 3 |
| Argument of perigee | 0 deg. | 0 | +/- 180 | +/- 180 |
| Longitude of ascending node | see table | /- 5 deg. | +/- 2 | +/- 2 |
| Right Ascension of ascending node | table | +/- 5 deg. | +/- 2 | +/- 4 |
| Period | 717.9882 min | |||
| Nodal regression rate | -0.04187 deg./day |
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