07 44874e 07 44874e 07 265597 265597 265597 265597

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Unformatted text preview: 0 0.000 0.000 -50.074 -279.854 209.856 -17.944 E1 E2 E3 E4 0.000 0.000 0.000 0.000 1.000 1.000 1.000 1.000 -4.4874E-07 -4.4874E-07 -4.4874E-07 -4.4874E-07 26559.7 26559.7 26559.7 26559.7 42.374 42.374 42.374 42.374 0.000 0.000 0.000 0.000 11.746 -242.704 -119.234 -211.614 F1 F2 F3 F4 0.000 0.000 0.000 0.000 1.000 1.000 1.000 1.000 -4.4874E-07 -4.4874E-07 -4.4874E-07 -4.4874E-07 26559.7 26559.7 26559.7 26559.7 102.374 102.374 102.374 102.374 0.000 0.000 0.000 0.000 53.586 159.926 -80.094 -49.954 NOTE (1): δi is relative to 0.30 semi-circles (54 degrees) NOTE (2): The (Ωo) values place each satellite orbit at its respective mean constellation orbit plane Tolerances/operational ranges for nominal orbit insertion and continuing orbit maintenance are as follows: • Groundtrack Equatorial Crossing: ± 2° • Eccentricity: 0.00 – 0.02 • Inclination: ± 3° • Semi-major Axis: ± 50 kilometers for Block IIR, ± 17 kilometers for Block II/IIA • Longitude of the Ascending Node: ± 2° • Argument of Perigee: ± 180° Note that orbit insertion error following launch can cause any of these parameters to exceed the required tolerance. Stationkeeping is not performed to maintain eccentricity or inclination. Page A-6 October 2001 A-2.1.2 GPS SPS Performance Standard Current Operations Nominal Constellation The information presented in Table A-2-1 represents a set of constellation design objectives established before the launch of any of the current operational satellites. The term “current operations nominal constellation” is used to distinguish what is considered the “optimum” constellation using current on-orbit assets from the “nominal constellation plan” established in Table A-2-1. Table A-2-2 identifies values for an almanac that represents the current operations nominal constellation as of the epoch time. The current operations “nominal” constellation is defined based upon annual updates from the system operator. The current operations policy is to update target Geographic Longitude of the Ascending Nodes (GLANs) on a yearly basis, to compensate for the effects of nodal regression. As can be seen, parameters reflect the actual state of the current constellation, with variations evident in eccentricity, inclination, and semimajor axis based upon the launch insertion errors unique to each satellite. Table A-2-2. Current Ops Nominal Constellation, Time of Almanac: 9/24/2000 17:04:00.00 Orbital e Mo δi (1) Ωdot (degrees/ A (meters) Ωo ω Position (degrees) second) (degrees) (degrees) (degrees) 0.0109 0.119 -4.499E-07 26,559,644 161.721 36.798 44.569 A1 0.0083 -0.296 -4.531E-07 26,561,421 159.421 -119.910 93.112 A2 0.0078 0.921 -4.414E-07 26,559,861 164.474 109.126 76.412 A3 0.0144 -0.039 -4.512E-07 26,557,536 160.671 -154.334 7.860 A4 B1 B2 B3 B4 0.0134 0.0054 0.0204 0.0023 -0.518 0.087 -0.496 -0.324 -4.780E-07 -4.728E-07 -4.754E-07 -4.761E-07 26,559,121 26,558,935 26,559,765 26,558,985 -140.488 -138.307 -141.277 -140.141 34.131 81.925 -119.701 12.779 -140....
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