My understanding is that there's a bunch of automated triggers --- e.g. if the vehicle leaves its flight corridor, it's supposed to get terminated. That doesn't necessarily mean that it goes bang; for a vehicle like the F9, shutting down all the engines is fine in most circumstances.
However, there is also a Range Safety Officer with a hand on a big red switch (or at least, a metaphorical hand on a metaphorical switch). They're the final authority on whether the vehicle lives or dies.
The shuttle may or may not have had a self-destruct system in the orbiter itself; I'm finding conflicting references. The SRBs and tank certainly did; the RSO pushed the button after Challenger disintegrated on launch to stop the SRBs flying away.
Yes, pushing the button while the SRBs and tank were attached to the orbiter would have killed the crew. Being the RSO is a job for very sober, very thoughtful people.
However, there is also a Range Safety Officer with a hand on a big red switch (or at least, a metaphorical hand on a metaphorical switch). They're the final authority on whether the vehicle lives or dies.
The shuttle may or may not have had a self-destruct system in the orbiter itself; I'm finding conflicting references. The SRBs and tank certainly did; the RSO pushed the button after Challenger disintegrated on launch to stop the SRBs flying away.
Yes, pushing the button while the SRBs and tank were attached to the orbiter would have killed the crew. Being the RSO is a job for very sober, very thoughtful people.