Mysterious engine problem

[Valdez]

Sorry if I\'m being slightly lazy by surrendering the problem to you guys ;D but this has kind of stumped me.

As you can see below, there are three columns of four tanks strapped to each of three more columns of four tanks in the centre. The problem is about three minutes into the flight the middle engines stop firing, but the outer ones continue. I\'ve placed pumps in various places to try and supply the central ones to no avail. It doesn\'t matter too much (it gets into orbit fine) but the problem still niggles me. Do any of you have any suggestions? I don\'t know why each engine won\'t use the four tanks above it when I take all the pipes away - they seem to insist on transferring fuel.

And the .craft file: http://www./?hucoyt9qv7hut79

Thanks for reading, sorry if the answer is painfully obvious.

[Clouds]

Not obvious, no. Even though fuel tanks aren\'t marked as crossfeed-capable, they will feed fuel from parent tanks to child tanks (i.e. in the order you attached the tanks) if they are connected to each other. So, the middle ones stop firing because all the engines are draining from the center tanks at first and those run out quickly, but only the outer engines can drain from the outer tanks (and fuel pipes won\'t fix things because the game doesn\'t allow circular flows). You\'ll have to put something that doesn\'t feed fuel between the inner and outer columns, for example a structural pylon.

[Vanamonde]

from parent tanks to child tanks

Is that why this happens? I was wondering if the inner engines were working harder because they bore more of the weight, or something like that. Nice to know.

[Markus Reese]

What happens I noticed is when engines are direct physically attached like that, it seems that the outer ones draw fuel from the inside connector ones. I only think that because it seems of the fast rate of consumption.

[Valdez]

Thanks for the help.