Does the Falcon 9 first stage use an explosive FTS?
An FTS can operate in many different ways. The key goal is to terminate thrust, break up large chunks of burny stuff, and avoid killing people.
A solid booster, you can just blow the cap off the front, and now you have terminated thrust (It blows out both ends, no net thrust). But you might also want to split it down its length so as to reduce the size of burning chunks of propellant.
A liquid fuel tank, you can run explosives down the length of it, to unzip the tank when needed.
A liquid fueled engine, if you trust the engines, you can kill the turbopumps, no more thrust. Or maybe you can quench the ignition, and run the turbo pumps to empty the tank.
There was some discussion around the Falcon 9R-Dev1 loss that the FTS system was not explosive, rather it just ran the tanks dry, killing thrust.
What does the production Falcon 9 first stage use?
Ultimate reason for asking is a short lived video was available that showed the failed landing on the CRS-6 mission, as the stage touched down, tipped over, it started to burn, then something clearly went kaboom, and things exploded outward. I was wondering if that was the FTS going off.
Watch the end of this video to see the explosions.