After a successful landing of the SRB-version without payload I'm trying to get the 42t orange tank into orbit, but the shuttle keeps tipping over to a heading of 0° (read: direction of external tank+boosters) right from the launch pad. Also, it barely gets off the launch pad which I assume is by design since the shuttle has a TWR of 1.21 when fully wet. I checked all tanks to make sure they are full as per the description in the OP. I'm at 533t dry and 887t wet. Edit: Just wanted to load the STS-7 to try the LF version but KSP 1.0.4 tells me "Not compatible with this version of KSP" Problem solved: I just now realised that the outher tanks don't have fuel lines going to the middle tank. Well, that's probably because they're just for aesthetics For future derps: Don't fill the outer external tanks. They just hide the SRBs and make the Shuttle look more realistic Just had my first successful 42t Mission with a textbook landing (thx to a lot of luck, obviously)