I saw the Ariane 6 animation, and I noticed, that the upper stage spins before deploying the satellites. Why are they doing this? Is it necessary or is it possible to successfully deploy a satellite to orbit without spinning it? Are the satellites spinning throughout their mission or they will stop spinning after reaching their desired orbit?
1 Answer
It's a stabilization technique. I'm not sure what you mean by "is it necessary"...they don't do things "just because" in rocketry. It's an alternative to three-axis stabilization.
The satellites are usually despun after the burn(s), often by the amusingly named "yo-yo de-spin". (good animation at link)
-
$\begingroup$ By "is it necessary" I mean is it possible to successfully deploy a satellite to orbit without spinning it. $\endgroup$– zbarniApr 25, 2015 at 14:21
-
2$\begingroup$ Sure, they could use a three-axis stabilization system. Like all things aerospace, it's a tradeoff between cost, weight, schedule, and performance for the particular application. Back in the days when Shuttle deployed comsats, PAMs were spun, and IUSs used three axis stabilization. $\endgroup$ Apr 25, 2015 at 14:46