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Ars Technica's Rocket Report: China discovers grid fins, NASA acknowledges Starship program says:

China experiments with grid fins. The launch of a Long March 2C from Xichang last week included a first use of grid fins by China, SpaceNews reports.

and that link in SpaceNews says:

Launch of a Long March 2C from Xichang last week included a first use of grid fins by China to minimize the threat posed by the spent first stage to populated areas downrange.

How do these statements reconcile with all of the photos of grid fins on Long March rockets shown in the following questions? Is this a blunder or are there some subtleties I'm missing here?


enter image description here enter image description here

left: from http://www.cctv-america.com/2016/10/14/heavenly-vessel-chinas-shenzhou-11-ready-for-liftoff right: screen captures from the YouTube video Launch of Manned China Mission with Shenzhou 11 to Tiangong-2. Click for full size or visit the linked questions for more details.

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    $\begingroup$ The grid fins used to be on a simple hinge for deployment, so on/off. I think the novelty is movable grid fins that can be used for steering. Although thats just speculation/my interpretation. $\endgroup$ – Polygnome Aug 2 at 22:32
  • $\begingroup$ I'm guessing but maybe the novelty is this part: " to minimize the threat posed by the spent first stage to populated areas downrange". Maybe they are deploying grid fins on the first stage just to make it crash in a less populated area. IIRC the grid fins on the Soyuz and derivatives are usually for use in aborts. Edit- after actually reading the link I'm pretty sure that's what they are talking about. $\endgroup$ – Organic Marble Aug 2 at 22:41
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It's pretty rare to see popular news articles get technical details right, and this is no exception.

The grid fins referred to in earlier QAs here are, as Polygnome notes, not maneuverable; they just act as passive stabilizers during LES aborts for the shroud-enclosed Shenzhou spacecraft. (See also this QA regarding the Soyuz grid fins.)

The new article is about active grid fins mounted on an interstage (that presumably stays with the first stage) to steer it after separation. From the SpaceNews article:

According to CASC, a team of one dozen members with an average age of under 35 carried out the research and development of the grid fins, which needed to be able to unlock, extend and rotate while also resisting high temperatures and pressures.

So this is likely the first use of active grid fins on a Chinese booster stage, but is not the first use of grid fins of any kind in the Chinese space program.

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  • $\begingroup$ There is some new news about Long March grid fins here and here. $\endgroup$ – uhoh Nov 7 at 0:47

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