I've noticed that the fuel gauges do not go down even if the airplane flies thousands of miles.  I've fiddled with all the boost pump switches and the bypass valves and the fuel indicators don't move.  I've reset the aircraft  and tried different variants.  Same thing.

Lordish

boeing247 wrote on Mar 2^nd, 2011 at 6:38am:


It's a good question.

I never had any kind of problems with C-130's fuel gauges. They work fine.

Pinatubo.

Flying the C-130X one of the issues I've noticed is that the fuel is loaded in pounds (US) and the panel is indicating the fuel burn rate in KGPH.   I can fill all the tanks and externals and register a 13,000 lbs per hour burn rate, that is Double what the plane should burn.   1,000 to 1,100 should be normal cruise with maybe 1,500 lbs per hour per engine on climb out.

LloydC130,

You have to properly manage the fuel with the pumps and bypass valves for the fuel to be taken from the tanks. If you leave all the bypass valves open and all the pumps on, it will take from the main tanks first. then start pulling from other available tanks. If the pumps for the aux and ext tanks are not on, it will never take from them even if they are full. Play with the bypass valves and pump switches to get a feel for what positions they need to be in for the fuel to be drawn from a specific tank. I regularly pull fuel from belly tanks for both engines to balance the main tanks with the wing tanks. About the only thing I have never figured out is how to transfer fuel from one tank to another. I do not think that is possible, but not a problem since you can use any tank to supply fuel to any engine.

Dave

There was a comment in a thread somewhere about the real aircraft would empty tanks based on pressure differential of the pump. If one pump was a little stronger, it would overide the others. This does not occur in FSX. I normally keep the bypasses closed (Horizontal) and all the pumps on so the engines will draw from their own individual tanks. If I need to balance the fuel I combine the tanks (move valves vertical) and turn off the pump of the tank I do not want to draw from, this causes both engines on a side to draw from the tank with the pump on. The same can be done for the Aux and Ext tanks. Put all the valves on a side to vertical then turn off the pumps on the tanks you do not want to draw from leaving the Ext or Aux tank pump on to draw only from that tank till the level drops to where you want it. Be careful about the valves and switches, as in, don't turn off a pump until you verify another pump is on to replace it. If you turn a valve off and the pump off that engine will have nowhere to get fuel from and die :0

I normally separate the right and left system with the center valve to the off (horizontal) position.

Thanks Sieggie, that method works great. Finally I can use the fuel in the ext and aux tanks 

I have not tried that to see if Capt Sim coded higher pressure on the Ext and Aux tanks. Would be neat but if not just switching off the wing and mains also works fine. You just have to pay closer attention not to empty the ext/aux without turning the wing/main back on or you get to practice inflight engine restarts :0

Dave

Uhhhm, thats not the opposite, that is exactly what I said. the aux tanks are the inboard-most tanks on the aircraft. They are burned first. Next come the externals. One reason for this is in the event of a valve or pump malfuntion in the externals, you will always have your mains which can gravity-feed to the engines if needed. this allows you time to divert if you have an external tank system failure that leaves you unable to use the fuel in that tank. You are exactly right (as was I) about keeping the wings heavy by keeping fuel in them. Primary Fuel Management dictates having not less than 6400 lbs in #2 & 3 tanks and not less than 7060lbs in #1 & 4 tanks if the aux's and external have any useable fuel in them. Tanks #1 & 4 should always have 500-1000 lbs more fuel than #2 & 3.
Additionally, symmetrical tanks should be within 1000lbs of each other and each wing collectively shoud be within 1500lbs of the other wing.

But again, I dont think structural wear is an issue on FSX aircraft...