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Comment by exDM69 | Hacker News Reader

> ... if you're designing man-rated systems, you like the big boosters to be liquid fueled because you can turn them off if needed ...

The SRBs had a way to turn them off by opening two exhaust ports near the top that would let the gasses out and neutralize the thrust.

But it's still a bit iffy, which is why cryogenic liquid fuels are the most common choice for human-rated launchers.

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Errr, I should have said "(gently) throttle down", since that's potentially in the menu of options for liquid fueled rockets. What you're talking about sure sounds like an inherently violent deceleration. And the tops of those SRBs are uncomfortably close to the tank and the LOX tank in it at the top....

As you say, "a bit iffy", at the very minimum.

Knowing little about this stuff, would it not be possible, and preferable, to eject them? Also, how realistic would it be to turn off liquid boosters, as they seem to usually fail with an immediate explosion?

Given the massive thrust they produce, and how close they are to delicate things like the tank, it's hard to imagine a system that could possibly work. It would be exquisitely difficult to get the vectors just right, so they wouldn't bush against the tanks or worse, and even if you pull that off, their exhaust will have bad effects as they pass by.

Short of not using them at all, exhaust ports at the top as mentioned by exDM69 sound like least worst option.

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