[ben_w]

While the FTS needs improvement, my (limitied) understanding is that its ineffectiveness was due to the fuel tank being almost empty at the time, and while in extremely thin air.

(But this is what I get as an untrained watcher of Scott Manley videos, I'm not a rocket scientist nor a pilot so I assume I only half-understand what he says, and what he says is necessarily a summary or the videos would be x10 longer).