> Yes, for most of the booster return it’s ‘gliding’ with the rocket engines completely shut down. Watching the video, it looked like the bottom of the rocket

> Yes, for most of the booster return it’s ‘gliding’ with the rocket engines completely shut down. Watching the video, it looked like the bottom of the rocket was glowing hot, but the engines were cool. I imagine that means they were probably running some amount of methane through the engine bells to cool them.