- Apr 16, 2011
- Reaction score
[ame="https://youtu.be/00Kz94aMaCc?t=2413"]LIVE: Ariane 5 Rocket Launches SES-14 & Al Yah-3 Satellites (Flight VA241) - YouTube[/ame]
I must admit that I don't see any tears..
http://www.arianespace.com/press-release/independent-enquiry-commission-announces-conclusions-concerning-the-launcher-trajectory-deviation-during-flight-va241/The Independent Enquiry Commission formed after the Ariane 5 launcher’s trajectory deviation during its January 25, 2018 mission issued its conclusions on Thursday, February 22. The anomaly’s cause is perfectly understood and recommendations are clearly identified. Arianespace and ArianeGroup are immediately implementing the Independent Enquiry Commission’s recommended corrective measures. The current Soyuz and Ariane 5 launch campaigns are continuing at the Guiana Space Center in French Guiana for the two launches planned in March.
oops... :uhh:Given the special requirements of this mission, the azimuth required for the alignment of the inertial units was 70 degrees instead of 90 degrees, as is most often the case for missions to geostationary transfer orbit. This gap led to the 20-degree shift to the south in the launcher trajectory from the initial seconds of flight.
Can someone explain this 70 degree vs 90 degree business? What were these 'special requirements'?
Except that Ariane launchers can't have a gimbal lock. They have no stable platform. :lol: They use a strap-down navigation system. That is also why it is easy to calibrate it wrong - there is nothing mechanic moving that could give a hint of a wrong alignment.
So it had a pure inertial guidance system which got deviated by 20 degrees? How common is that? I always assumed that , aside from the pre-programmed trajectory. modern rockets would be "aware" of their position. Perhaps even with calculations as to what corrections would be needed to stay on course.