So I've been working on a project that has gone to shit, scope isn't clear and deadline is too tight. Developers get dropped into the team to "make it work"

Currently I think it is unavailable to succeed within the deadline. But this got me thinking, how do you actually save such a project? Could a good project lead save a chaotic project? If so... How? (And more importantly to me, how does one become a good project lead, do I need 10+ years of programming experience?)