2018-012A
AirbusDS E3000e, with Ku, C and Ka for DTH in Americas and mobile comms. 47.5W replacing NSS 806. Mass 4200 kg.
Flight VA241 took off on time, but headed on entirely the wrong launch azimuth, and the rocket delivered the payloads to a 20 degree inclination orbit instead of the planned 3 degree one. Because of the incorrect trajectory, ground controllers lost telemetry around the time of ESC-A ignition, leading to fears the mission was entirely lost - but the satellites were later found in orbits with the correct apogee and perigee, and the wrong inclination.
The investigation report confirms that a single wrong number was responsible for the incorrect orbit achieved by Ariane V241/L5101. The inertial reference system (IRS) was aligned at the usual 90 degrees azimuth, but for this mission - targeted at a slightly different transfer orbit than usual - 70 degrees should have been specified.
A request by SES for its payload to be ejected at 90 deg to the flight direction to minimize contamination led to a need to change the zero point of the IRS (apparently to avoid a coordinate singularity) and this led to the 70 degree requirement.
| SES-14 | |||
| Date | Time | Event | Orbit |
|---|---|---|---|
| 2018 Jan 25 | 2220 | Launch by Ariane 5ECA L5101 | CSG ELA3 |
| T+0:07 Liftoff | |||
| T+2:19 EAP sep | |||
| T+3:18 Fairing sep | |||
| T+8:51 EPC MECO | |||
| T+8:58 EPC sep | |||
| 2229 | 9:01 ESC-A burn | ||
| 2244 | T+24:46 ESC-A MECO | ||
| 2247 | T+27:05 SES-14 sep | ||
| 2253 | T+33:22 SYLDA sep | ||
| 2255 | T+35:07 Al Yah 3 sep | ||
| 2018 Jan 26 | 780.28 231 x 43164 x 20.7 | ||
| 2018 Jan 27 | 783.19 334 x 43199 x 20.6 | ||
| 2018 Feb 7 | 840.86 1188 x 45077 x 19.3 | ||
| 2018 Mar 1 | 1020.65 4187 x 50216 x 16.4 | ||
| 2018 Mar 16 | 1158.63 6898 x 53430 x 14.6 | ||
| 2018 May 9 | 1376.02 19580 x 49625 x 7.6 | ||
| 2018 May 12 | 1381.77 20396 x 49036 x 7.4 | ||
| 2018 May 23 | 1397.63 23585 x 46475 x 5.7 | ||
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