Built in orbit Duna craft failure due to strange anomaly.

[Leszek]

https://www.dropbox.com/s/4xso71alxllxsuh/screenshot6b.png?dl=0

I have built a Duna orbiting spacecraft in orbit. This craft is a tractor type space craft and the tractor portion has its gimbals disabled. This operation took several hours and multiple launches with early game technology. When all was set and I was ready to go, the craft lost control. After a bit of a confused investigation I found that one engine in a set of symmetrically placed engines doesn't get any fuel. (See screenshot, notice the staging shows it has no fuel. The shut off engine is a Soyuz and is supposed to be off for the duration of the mission.)

I can't find any reason for this as the whole thing is symmetrical. There aren't fuel lines, but the other 3 don't need them. Any ideas on what is going on? Bug?

P.S. All 4 engines worked fine when I put the ship into orbit. I used them to circularize and refilled the tanks with a tanker later on.

Edited October 9, 2015 by Leszek

[Phil deCube]

I don't know what the cause of your problem is, but the TAC Fuel Balancer mod might be an answer. It will automatically balance fuel in all tanks, if you ask it to.

[Right]

I've accidentally disabled fuel flow from a tank and had something similar happen before

[Leszek]

I have had to re-enable cross feed every time I add a fuel tank module to the craft. Also many ships have docked and undocked including a tanker. Having said that the engines on the main propulsion module do have a little bit of fuel. There is a small tank the engine is directly connected to that provides a bit of thrust but when the other engines are taking fuel from the last tank in the ship this one engine is taking fuel from only this attached tank. The screenshot is what it looks like when the attached tank is empty or shut off.

Most strange.

[Right]

Yeah TAC fuel balancer might be you're best bet, you can override the flow behavior.

Is the propulsion module a single craft which was docked?

[Leszek]

Yeah TAC fuel balancer might be you're best bet, you can override the flow behavior.

Is the propulsion module a single craft which was docked?

Yes a single craft with limited fuel, probe core, communications for remote tech, some battery power, solar power, and pod for two Kerbals which was empty at launch and doesn't have control capability. The next 4 modules are just tanks with docking ports and radiators attached. The last module at the end is the science module and attached Soyuz which acted as a space tug to dock the science module.