[size=+2]Fuel tanks[/size]
[size=+1]The main tank[/size]
We all know that our ships have one or more fuel tanks from which the frame shift drive draws fuel when jumping between systems. The amount of fuel available in these tanks is shown in a thick bar on the right of the HUD. When we plot a jump, a portion of that bar turns blue to show how much fuel will be expended by the jump, and after the jump the bar shrinks accordingly.
This bar represents the amount of fuel in the main tank. If you've ever allowed it to run out you will have seen and heard the message "main fuel tank drained" warning you of that fact.
[size=+1]The reserve tank[/size]
There is another, thinner bar, shown above the main tank bar. This bar represents the reserve tank. The reserve tank is steadily drained by active modules on your ship. The rate of drain is shown above the bar. When the reserve tank is empty, fuel is automatically taken from the main tank to top it back up. Unless the main tank is empty, in which case you need to call the Fuel Rats because your ship is about to explode.
Fuel in the reserve tank cannot be consumed by the frame shift drive, although its mass does contribute to jump cost calculations. Furthermore, the reserve tank cannot be replenished by fuel scooping. If you are within the scooping zone of a star you can observe that the fuel scoop will deactivate when the main tank is filled. If the reserve tank runs empty while you are still in the zone, it will be topped up from the main tank and fuel scooping will briefly resume to replace the fuel which was moved to the reserve.
[size=+1]Why is the reserve tank important?[/size]
Needless to say, the fact that your ship cannot operate without fuel in the reserve tank is worthy of note, at least in an abstract sense. The automatic topup mechanism from the main tank makes the threat of ship destruction less ominous in most circumstances.
Apart from that, the mass of the fuel in the reserve tank does contribute to the fully laden mass of the ship and must be taken into account when calculating jump range and fuel cost.
Reducing the number of (time-consuming) hyperspace jumps is a common tactic in Buckyball races. When CMDR Alot travelled from Sol to Sagittarius A* in under two hours he optimised his route down to the level of plotting jumps that would only be possible with a particular amount of fuel in his reserve tank. I myself have won races by planning routes that required specific numbers of 10% refuels at stations.
As we shall see, the Refuel 10% action at stations does not simply refill 10% of the main tank size. It also refills 10% of the reserve tank. That extra fuel can be the difference between making a long jump or not being able to.
[size=+1]Determining the size of the reserve tank[/size]
When docked at a station which offers refueling facilities, we can choose to Refuel All or Refuel 10%. The amount of fuel actually purchased for a 10% refuel shows up in the journal file as a property of the RefuelPartial event.
When experimenting with 10% refuels and looking at the RefuelPartial events recorded in the journal, I made some observations.
Note that it is important that the main tank be at less than 90% capacity for this experiment. When the tank is 90% full, the Refuel 10% action will always top it up completely regardless of the actual amount of fuel present. It will therefore not be possible to break down the fuel allocation.
Example:
An Adder with an 8T fuel tank is refuelled by 10%.
The fuel dispensed is 0.836T.
10% of 8T is 0.8T.
Therefore 10% of the Adder's reserve tank size is (0.836 - 0.8) = 0.036T.
We conclude that the Adder has a reserve tank size of (0.036 x 10) = 0.36T.
[size=+1]Reserve tank sizes for every ship[/size]
Please feel free to check and correct. You can imagine how tediously boring this research was, so mistakes are quite possible.
[size=+1]The main tank[/size]
We all know that our ships have one or more fuel tanks from which the frame shift drive draws fuel when jumping between systems. The amount of fuel available in these tanks is shown in a thick bar on the right of the HUD. When we plot a jump, a portion of that bar turns blue to show how much fuel will be expended by the jump, and after the jump the bar shrinks accordingly.
This bar represents the amount of fuel in the main tank. If you've ever allowed it to run out you will have seen and heard the message "main fuel tank drained" warning you of that fact.
[size=+1]The reserve tank[/size]
There is another, thinner bar, shown above the main tank bar. This bar represents the reserve tank. The reserve tank is steadily drained by active modules on your ship. The rate of drain is shown above the bar. When the reserve tank is empty, fuel is automatically taken from the main tank to top it back up. Unless the main tank is empty, in which case you need to call the Fuel Rats because your ship is about to explode.
Fuel in the reserve tank cannot be consumed by the frame shift drive, although its mass does contribute to jump cost calculations. Furthermore, the reserve tank cannot be replenished by fuel scooping. If you are within the scooping zone of a star you can observe that the fuel scoop will deactivate when the main tank is filled. If the reserve tank runs empty while you are still in the zone, it will be topped up from the main tank and fuel scooping will briefly resume to replace the fuel which was moved to the reserve.
[size=+1]Why is the reserve tank important?[/size]
Needless to say, the fact that your ship cannot operate without fuel in the reserve tank is worthy of note, at least in an abstract sense. The automatic topup mechanism from the main tank makes the threat of ship destruction less ominous in most circumstances.
Apart from that, the mass of the fuel in the reserve tank does contribute to the fully laden mass of the ship and must be taken into account when calculating jump range and fuel cost.
Reducing the number of (time-consuming) hyperspace jumps is a common tactic in Buckyball races. When CMDR Alot travelled from Sol to Sagittarius A* in under two hours he optimised his route down to the level of plotting jumps that would only be possible with a particular amount of fuel in his reserve tank. I myself have won races by planning routes that required specific numbers of 10% refuels at stations.
As we shall see, the Refuel 10% action at stations does not simply refill 10% of the main tank size. It also refills 10% of the reserve tank. That extra fuel can be the difference between making a long jump or not being able to.
[size=+1]Determining the size of the reserve tank[/size]
When docked at a station which offers refueling facilities, we can choose to Refuel All or Refuel 10%. The amount of fuel actually purchased for a 10% refuel shows up in the journal file as a property of the RefuelPartial event.
Code:
{ "timestamp":"2017-09-10T21:24:30Z", "event":"RefuelPartial", "Cost":42, "Amount":0.836000 }
- When the ship's total fuel level is 90% or more, the Refuel All and Refuel 10% actions have the same cost.
- When the ship's total fuel level is below 90%, a 10% refuel always costs the same amount of credits and dispenses the same amount of fuel given the same size of main tank.
- When the ship's total fuel level is below 90%, a 10% refuel always dispenses more than (size of main tank) x 10% fuel.
- Drain the main tank below 90%, for example by making one or more hyperspace jumps.
- Purchase a 10% refuel.
- Consult the journal to see how much fuel we actually purchased.
- Subtract (size of main tank) x 10% from the amount recorded in the journal.
- Multiply the remainder by 10.
Note that it is important that the main tank be at less than 90% capacity for this experiment. When the tank is 90% full, the Refuel 10% action will always top it up completely regardless of the actual amount of fuel present. It will therefore not be possible to break down the fuel allocation.
Example:
An Adder with an 8T fuel tank is refuelled by 10%.
The fuel dispensed is 0.836T.
10% of 8T is 0.8T.
Therefore 10% of the Adder's reserve tank size is (0.836 - 0.8) = 0.036T.
We conclude that the Adder has a reserve tank size of (0.036 x 10) = 0.36T.
[size=+1]Reserve tank sizes for every ship[/size]
Please feel free to check and correct. You can imagine how tediously boring this research was, so mistakes are quite possible.
Ship | Tank |
Hauler | 0.25 |
Sidewinder | 0.30 |
Eagle | 0.34 |
Adder | 0.36 |
Imperial Eagle | 0.37 |
Type 6 | 0.39 |
Keelback | 0.39 |
Viper Mk III | 0.41 |
Imperial Courier | 0.41 |
Viper Mk IV | 0.46 |
Asp Scout | 0.47 |
Cobra Mk III | 0.49 |
Diamondback Scout | 0.49 |
Mamba | 0.50 |
Dolphin | 0.50 |
Cobra Mk IV | 0.51 |
Diamondback Explorer | 0.52 |
Type 7 | 0.52 |
Vulture | 0.57 |
Krait Mk II | 0.63 |
Krait Phantom | 0.63 |
Asp Explorer | 0.63 |
Fer-de-Lance | 0.67 |
Federal Assault Ship | 0.72 |
Imperial Clipper | 0.74 |
Alliance Challenger | 0.77 |
Alliance Crusader | 0.77 |
Type 10 | 0.77 |
Type 9 | 0.77 |
Alliance Chieftain | 0.77 |
Orca | 0.79 |
Beluga | 0.81 |
Federal Gunship | 0.82 |
Federal Dropship | 0.83 |
Python | 0.83 |
Anaconda | 1.07 |
Federal Corvette | 1.13 |
Imperial Cutter | 1.16 |
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