Interstellar travel and the crew

[StarSword]

The only viable way of going between the stars with a human crew and real technology to me appears to be sending out a large fleet of multiple vessels, each with some specialization but no one vessel being ‘key’ and each vessel having a margin for crewmen from the other ships, as well as new births exceeding deaths. That way even if one is totally destroyed by say, an unexpected asteroid moving too fast to be detected in time, you aren’t screwed. If you had ships along with foundries and a bunch of computer controlled machine tools, plus highly advanced 3D printers you’d be able to repair or replace nearly anything. Larger more important items like reactors, might be carried as partly finished blanks, and trimmed down when needed.

This kinda reminds me of the situation in Battlestar Galactica, at least the original.