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Near the top of the Long March 2F rocket (middle of the fairing?) that launched today with the Shenzhou-11 crew, there are four square wafffle-like structures that remind me of grid fins.

What are they?

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above x2: from http://www.cctv-america.com/2016/10/14/heavenly-vessel-chinas-shenzhou-11-ready-for-liftoff

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above x2: screen captures from the YouTube video Launch of Manned China Mission with Shenzhou 11 to Tiangong-2.

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  • $\begingroup$ Could they be part of a cooling system for all of the electrical systems that are active inside the closed fairing perhaps? $\endgroup$ – uhoh Oct 17 '16 at 7:22
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    $\begingroup$ The Shenzou was originally based on purchased Russian technology - parts of the spacecraft are based on Soyuz components. These four panels look exactly like the "fins" that unfold when the Soyuz launch escape system fires, to keep the escaping components pointing up while the rockets fire. (Some of your other questions about this spacecraft also apply to Soyuz by the way - such as the window, and the shroud that covers the spacecraft during launch.) $\endgroup$ – Andy Oct 17 '16 at 7:36
  • $\begingroup$ @Andy if that is the answer, why not post it as an answer instead of leaving the answer as a comment? $\endgroup$ – uhoh Oct 17 '16 at 7:39
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    $\begingroup$ the Soyuz escape firing sequence is a bit complicated (as there are separate steps for escape, and for shroud jettison) and I don't know any good references - so I didn't want to post an incomplete answer (also not sure exactly how similar Shenzou is - there are various differences to Soyuz I believe). $\endgroup$ – Andy Oct 17 '16 at 7:56
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    $\begingroup$ Drag brakes / grid fins used in abort seqence. $\endgroup$ – Organic Marble Oct 17 '16 at 9:44
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From Spaceflight101:

For Shenzhou Missions, a stretched version of the typical Long March fairing is used ... Four aerodynamic stabilizers are attached to the upper part of the fairing that is part of the Launch Escape System in a escape scenario, those would deploy to stabilize the vehicle while flying under the Launch Abort Engines. The Fairing’s ‘wings’ are in a stowed position for flight.

http://spaceflight101.com/spacerockets/long-march-2f/

As with Soyuz, these are grid fin stabilizers; here's a clear picture:

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It doesn't look like the stabilizers are articulated beyond hinging out to a deployed position, so unlike the grid fins found on e.g. Falcon 9, they don't give any active steering capability, they just slow the capsule and keep it oriented into the airstream, like the feathers of a badminton shuttlecock.

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  • $\begingroup$ It looks like its time to start reading up on grid fins. That's a beautiful photo - it shows very clearly what's going on. Actually it shows a lot of other interesting things too. Thanks again! $\endgroup$ – uhoh Oct 17 '16 at 14:42
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    $\begingroup$ Anticipating some future questions, the launch escape tower has a small set of engines for jettisoning the tower by itself, and a larger set for taking the Shenzhou with it. The nozzles on the left side of the fairing might be pitch motors for launch escape, to turn the escaping craft out of the line of the booster acceleration, but that's just a guess. $\endgroup$ – Russell Borogove Oct 17 '16 at 14:47

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