Fuel

**Fuel** or **propellant** is a very vital part of a rocket. It allows Engines to run, and the rocket to lift off. More Fuel Tanks means more fuel for a stage, but it doesn't mean your rocket would liftoff with tons of fuel. More fuel also means increasing your rocket's weight and lowering its Thrust to Weight Ratio or TWR, making it impossible to liftoff with all this mass in the rocket.

Fuel Tanks are tanks that contain rocket fuel, and it is very important during long missions.

## Amount

There are lots and lots of varieties of fuel tanks, from the small square fuel tank, the 5t variant, to the heaviest of them all, to the 120t variant, which it is 12 wide. Note that the Fuel Tank's mass is 90% from the fuel and 10% from the tank itself. So a 10t fuel tank actually has 9t of fuel. Fuel indicators are bars or even percentages, but the current version, supports bars instead.

When you run out of fuel in your rocket, a notification called "**Out of [liquid/solid] fuel**" appears, meaning the fuel tanks had ran out of fuel inside them. If it is a stage of a rocket, you can separate it, using Separators or Docking Ports, then move on into the next one.

A rocket does not need to only have have one stage; it must have multiple stages to get into its destination.

If the rocket is low in fuel, get to a refueling station. The other way is to **quicksave edit**, which means editing a quicksave to edit the amount of fuel it has in the fuel tanks inside, although this is considered cheating.

## Importance

The importance of fuel is to power rockets to their destinations, like getting into orbit, docking to spacecraft, and reaching the other planets such as the Moon and Mars.

When adding some mass to end payload, the amount of fuel to send this additional payload mass to destination grows dramatically due to the fuel mass cascade effect.

## Transferring Fuel

*Main article: [[]]*

It is possible to transfer fuel from one tank to the other. To transfer fuel, tap 2 fuel tanks (that are separate from each other), and to stop the transfer, tap one of the fuel tanks. This is explained more at the Fuel Transfer page.

## Types of fuel

There are two types of fuel:

* **Solid fuel**: This propellant is used widely on solid rocket boosters. These boosters can't be throttled or stopped once activated, and will shut down when they run out of solid fuel.
* **Liquid fuel**: This propellant is used by many rockets. Liquid fuel feeds into a liquid-fuel engine. Rocket engines burning this fuel can be throttled and stopped instantly.

## Bugs

* Using a solid rocket booster, then reverting 30 seconds into the past gives infinite fuel(The flame wouldn’t be shown but the booster will still produce thrust)

## Trivia

* Real life fuel is mostly a mixture of some liquid and oxygen (or O2), most commonly hydrogen–oxygen mixture (H2–O2), which is used in the Space Shuttle.
* Engines in-game use different types of fuel, such as kerosene–oxygen mixture for operating the Hawk/Titan Engine, a methane–oxygen or hydrogen–oxygen mixture for the Valiant/Kolibri Engine, a hydrogen-oxygen mixture for the Frontier Engine, and xenon for Ion Engine.
* Solid rocket boosters in real life slowly become less powerful as they run out of fuel.