airplane fuel position and control

[bigbangnet]

Is there a way to easy manage fuel in airplanes ? Right clicking on the fuel tanks is not really efficient. Also why do I have no option to put fuel in wings just like in today's aircraft...or create a fuselage that gives me the ability to put fuel in the fuselage so I can make sure the center of mass and lift is always in the center. Right now if I add 2 fuel tanks or more, it becomes problematic when one of my fuel tanks is losing fuel, the center of mass and lift change and I become dropping bomb

[The_Rocketeer]

It's all about balanced fuel distribution and ensuring even draining.

For a single-tank plane, when designing your plane, start with just a fuel tank. Check where the CoM is, and try to add parts in turn to the front and back of the tank, so that the balancing point for the plane stays close to the middle of the tank. This will minimise CoM movement due to burning off fuel.

For multi-tank planes, the balancing rule applies the same, but it's crucial to make sure that the engines draw fuel from the middle tank (with the CoM in it) first. Consequently, you need to make sure the engines aren't attached directly to the tanks (unless you have 1 engine per tank), and use fuel hoses so that the fuel reaches the engines from the middle first. If you're using parallel tanks, it's only important that the CoM is in the middle on the x (front to back) axis - in other words, you don't need to put the CoM in a tank as long as it's between two tanks that are going to drain evenly.

Engines always draw from the furthest away tank (by number of part connections). If two or more tanks are equally far away, it will draw from them in a balanced way, but if one is nearer it will drain it empty first. This will move your CoM. Some parts won't let fuel flow through them, so watch out for that - these can be a help and a hindrance, but you can always work around them with fuel pipes if you know they're there.

Draining fuel doesn't change CoL, just CoM.

As for why parts have the functions they have and not others, that's just how the game's designed. If you really want fuel in the wings, there may be mods that do this, but actually wings are rarely in line with the CoM so you'd still have the same problem. Some... actually, most... fuselages do contain fuel.

Edited December 17, 2014 by The_Rocketeer

[Hodo]

Is there a way to easy manage fuel in airplanes ? Right clicking on the fuel tanks is not really efficient. Also why do I have no option to put fuel in wings just like in today's aircraft...or create a fuselage that gives me the ability to put fuel in the fuselage so I can make sure the center of mass and lift is always in the center. Right now if I add 2 fuel tanks or more, it becomes problematic when one of my fuel tanks is losing fuel, the center of mass and lift change and I become dropping bomb

This is one of my simple stock fighters from .25 that works in .90. It is a SSTO spaceplane but the same principles apply to it as do a standard airplane.

The fuel tank is pretty much centered on the CoM, so as it drains it will not affect the CoM by much if any at all. I think this craft the CoM shifts by about .1-.25m total.

[Red Iron Crown]

There are a few mods for managing fuel levels in tanks. I started with TAC Fuel Balancer (simple and effective), before moving to Goodspeed Fuel Pump (a bit more complex and flexible).