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From this video on YouTube:

enter image description here

What are those devices and what is their purpose?

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  • $\begingroup$ Do we need a tag for spacesuit, uniform, flying-clothes or perhaps "safety-spurs" ? $\endgroup$ – Criggie Feb 2 '17 at 7:22
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    $\begingroup$ "Pilot personal equipment"? $\endgroup$ – Steve Feb 2 '17 at 13:20
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These are part of the foot restraint system fitted to the seats used in the SR-71, later U-2 and some Space Shuttles. (They're all derived from the same basic design).

The spurs engage in two ball nipples that protrude from the lower part of the seat. The nipples are connected via cables to reels beneath the rear of the seat which pull the pilots feet in during the ejection sequence.

The seat separation sequence severs these cables (amongst other things) allowing the seat to drop away.

You can see the nipples on the lower part of this Space Shuttle seat:

enter image description here

Source:The Ejection Site

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    $\begingroup$ I figured they were related to ejection, but I also wondered about use of rudder pedals. The idea of cables makes a lot of sense. $\endgroup$ – Steve Feb 2 '17 at 1:06
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    $\begingroup$ Hmm... I'm now curious under what circumstances one could eject from the Space Shuttle. That seems like it would end very badly in almost any phase of flight, except maybe the last minute or so before landing. $\endgroup$ – reirab Feb 2 '17 at 4:46
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    $\begingroup$ After reading here, it looks like the pilot of the first Shuttle mission shared my concerns and the ejection seats were removed entirely after the first few flights. Apparently they were only ever installed on Columbia and Enterprise (the unpowered test craft) in the first place. $\endgroup$ – reirab Feb 2 '17 at 4:52
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    $\begingroup$ @reirab, in the first fatal accident, ejection seats would have actually likely helped—the break-up forces did not exceed 20g and the cabin held together and descended at subsonic speed, so ejection during the descent would have been within envelope. The envelope would still be inferior to launch escape system like capsule spaceships have and it's not clear it would be sufficient in case of on-ramp accident (like the LES did on Soyuz T-10-1. $\endgroup$ – Jan Hudec Feb 2 '17 at 19:07
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    $\begingroup$ @JanHudec Yeah, that's a good point about Challenger, actually, since the SRBs separated from the stack when the external tank began disintegrating. Normally, I would think that ejecting during launch would lead to a very unpleasant encounter with the exhaust plumes from the SRBs (and apparently the pilot of STS-1 shared that concern.) $\endgroup$ – reirab Feb 2 '17 at 19:43
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Those were attachments for the ejection seats leg restraints to be used when bailing out of the aircraft in an emergency.

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