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This video (a tour of the SpaceX factory by Elon Musk) suggests that the second stage of Falcon 9 has Draco thrusters as a Reaction Control System (RCS) (at 2:14), but I don't recall ever seeing them in photos:

For instance, in the following photos I don't see obvious covers for nozzles.

F9 second stage
This is an incomplete stage of course.

F9v1.1

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  • $\begingroup$ Do you mean attitude control thrusters (RCS)? $\endgroup$
    – Erik
    May 20, 2015 at 17:17
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    $\begingroup$ fixed the video link. $\endgroup$
    – Hobbes
    Aug 15, 2016 at 7:26

3 Answers 3

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According to the 2009 Falcon 9 User Guide, the second stage does have 4 Draco thrusters. I suspect this was done on the Falcon v1.0 only.

According to the Falcon 9 User Guide v2.0, the second stage has nitrogen gas thrusters (page 11-12) for pitch, yaw and roll control. They can also gimbal the main engine. I still haven't found photos of either configuration though.

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  • $\begingroup$ They are likely mounted around the Merlin/stage interface but I can't find a picture either. $\endgroup$ Mar 28, 2016 at 11:10
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On the sixth Falcon 9 (first in V1.1 configuration) launch for Cassiope there was a failed attempt to re-ignite the second stage again as a demonstration of required capability for GEO/GTO missions.

I cannot find a link to this specific detail, but there was a report I recall that they were going to fire at 90 degrees to the flight path, since they had no where to go really, and just wanted to test reigniting while in orbit.

In order to rotate a stage as massive as the second stage (23,000 kg empty) you need either fairly large gyros or some kind of attitude control system.

They do not have Draco engines on the second stage, but they do seem to have some kind of control system. Likely it is a cold gas nitrogen system, similar to what they have on the first stage and interstage.

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    $\begingroup$ I'm pretty sure Falcon 9's second stage is just 4-5 tons empty, not 23 tons. It could, however, be something like 17-20 tons if you factor in the heaviest possible payload attached to the second stage. $\endgroup$
    – radex
    Mar 28, 2016 at 19:20
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I don't think the second stage equipped with the reaction control system because the Dragon capsule has it (ref: Space Launch Report: SpaceX Falcon 9 Data Sheet - 2017 and 2019). I also don't see the system in an unofficial CAD model.

If the SpaceX want to reuse the second stage, I guess that it should have the reaction control system.

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    $\begingroup$ Not every Falcon has a Dragon for a payload. $\endgroup$ Jan 28 at 17:34

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