Rocketry Guide & Frequently Asked Questions
Base Game Mechanics & Mass Penalty
Base game rockets operate on engine efficiency and fuel weight, with range heavily restricted by dry weight penalties:
- Thrust Formula: Range (km) = (Fuel Mass × Engine Efficiency × Oxidizer Efficiency) + (Boosters × 12,000) - Mass Penalty.
- Mass Penalty: Under 4000kg, range loss equals weight in kg. Over 4000kg, range loss equals (Weight / 300)^3.2. This makes heavy cargo modules extremely range-restrictive.
- Solid Boosters: Add exactly 12,000 km of flat range, but add 1000kg to the rocket's dry mass.
Spaced Out! Height Stack budgets
The DLC introduces modular rockets where engines provide a physical height restriction:
- Height Limit: Each engine specifies how many tiles of modules it can support. A Radbolt Engine has a 32-tile budget, while a Sugar Engine only has a 20-tile budget.
- Staging: Heavy utility modules (like Large Liquid Cargo, 8 tiles) consume a massive portion of the height budget. Lightweight modules (Solar Panel, 2 tiles) allow you to save space for critical cabins.
Frequently Asked Questions
In the base game, your rocket's engine range gets penalized as rocket mass increases. If total mass is below 4000kg, the penalty is simply equal to its total mass. Once total mass goes above 4000kg, the penalty grows quadratically: Penalty = (Total Mass / 300) ^ 3.2. This causes a massive range penalty spike if you add too many heavy cargo bays or research modules, so you must carefully compute whether adding a solid booster is worth the mass.
For liquid engines (Petroleum, Hydrogen), the optimal ratio is exactly 1:1 by weight when using Liquid Oxygen, or 1:1 when using Solid Oxidizer (Fertilizer or Oxylite). However, Liquid Oxygen is twice as efficient, meaning you need half the weight of oxidizer for the same range. Always adjust your fuel and oxidizer tanks to be equal in weight for maximum range efficiency.
In the Spaced Out! DLC, rockets do not use range penalties based on mass. Instead, each engine has a specific 'height budget' (e.g. Radbolt Engine: 32 tiles, Sugar Engine: 20 tiles, Steam Engine: 23 tiles) and a max range. Every module you stack on top of the engine (capsule, solar panels, battery, cargo bays) has a physical height in tiles. The total height of the rocket stack cannot exceed the engine's budget, or the rocket cannot launch.
Oxylite is a solid oxidizer with an efficiency multiplier of 1.33x. Liquid Oxygen is a liquid oxidizer with an efficiency multiplier of 4.0x. Using Liquid Oxygen instead of Oxylite increases your range by 3 times for the same amount of fuel, making it crucial for late-game deep space exploration.