Propulsion modules are a type of active module which increase your ship's speed (at the cost of capacitor energy). Higher speed allows you to dictate the range at which combat takes place (optimising the effectiveness of your ship's weapons and/or reducing the effectiveness of enemy ships' weapons).
Afterburners and microwarpdrives
Afterburners (AB) and Microwarpdrives (MWD) are the most commonly used propulsion modules. Afterburners increase the ship's maximum speed by around 150%, while Microwarpdrives increase it by around 500%. Compared with Afterburners, Microwarpdrives use more capacitor energy, reduce the ship's total capacitor capacity, are shut down by warp scramblers, and are generally harder to fit.
There are different sizes of propulsion modules based on basic ship hull size. Using an undersized afterburner on a larger ship will cause the speed boost to become much smaller.
General guideline for module sizes:
- 1MN/5MN = Frigates and Destroyers (actual thrust is 1,500,000 N).
- 10MN/100MN = Cruisers, Battle Cruisers and Industrials (actual thrust is 15,000,000 N).
- 100MN/500MN = Battleships (actual thrust is 150,000,000 N).
- 10000MN/50000MN = Capital ships (actual thrust is 1,500,000,000 N).
The max velocity bonus listed in module info is only one factor in actual velocity increase. The maximum velocity of a ship using a propulsion module is
- V_max = V_base × ( 1 + V_bonus × ( Thrust / mass ))
In practice that last thrust/mass term is almost equal to one when using properly sized propulsion module and the new maximum velocity is just base velocity multiplied by velocity bonus of propulsion module.
Certain ships require certain size afterburner to function properly or heavily favor certain types of modules with hull bonuses.
It is possible to fit ships with oversized afterburners: 10MN on frigate/destroyer or 100MN on cruiser/battlecruiser. The high fitting requirement of larger afterburner usually makes this harder to do. In this case the full maximum velocity formula needs to be used.
Generally the resulting maximum velocity is close to normal sized microwarpdrive but the added bonus is that the oversized afterburner is not shut down by scramblers. The drawback is greatly increased ship mass which makes maneuvering harder.
The following skills directly effect afterburners and/or microwarpdrives.
- Acceleration Control 5% Bonus to Afterburner and Microwarpdrive speed boost per skill level.
- Afterburner 5% reduction to Afterburner duration and 10% reduction in Afterburner capacitor use per skill level.
- Fuel Conservation 10% reduction in afterburner capacitor needs per skill level.
- High Speed Maneuvering 5% reduction in MicroWarpdrive capacitor usage per skill level.
Micro Jump Drives
The Micro Jump Drive (MJD) is a propulsion module that instead of making the ship move faster it jumps the ship forward 100km in the direction it is facing. Upon arrival, the ship maintains its direction and velocity. Warp scramblers can be used to disrupt the module.
Micro jump drives can be used only on T1 and T2 battleships, combat battlecruisers, command ships and deep space transports. Marauders gain specific bonus encouraging use of this module.
Micro jump drives can be used offensively to close on a target or defensively to jump out.
Micro Jump Drive operation
When the module is activated the module spools up for 12 seconds. During this time the ship can not change its direction. The signature radius of the ship is also increased by 150% during the spool up time.
The jump is interrupted if the jumping ship is warp scrambled when spool up time ends. Bubbles, warp disruptors and warp core stabilisers have no effect on micro jump drives. Active bastion module also prevents the ship from jumping. Deactivating the module during spool up time has no effect.
After spool up period the ship jumps 100 km to the direction it is facing. The ship retains its velocity and locked targets through the jump. Other ships will also retain locks on the ship that jumped.
After the jump has been completed or aborted by scrambler the MJD module enters 180 seconds long cooldown period that must pass before the module can be used again. Even if the jump fails the module will enter cooldown period.
Micro Jump Field Generator
Micro Jump Field Generators (MJFG) are similar to Micro Jump Drives. But instead of jumping only one ship MJFGs jumps all ships in 6 km range of the ship using the module.
Only command destroyers can use Micro Jump Field Generators. It's not possible to use this module in high sec, it can't pull invulnerable targets (ships that have just undocked or just jumped through a gate and are still cloaked) and capitals are not affected by it.
Operation of MJFGs is almost identical to MJD operation. The only difference is that it jumps all vulnerable ships, drones, bombs etc. in 6 km radius. Scramblers can also prevent their targets from getting jumped. This way the ship with MJFG and some of the ships near it can be jumped, while others stay in their places. This can be used in various ways, for example: to split up hostile fleets respectively isolate targets, as a escape tool for fleets and to make slow sniper fleets move around the grid quickly, allowing them to "kite" enemies that would otherwise catch up with them. With several command destroyers the jumps can be chained, the long cooldown of 160s only applies to the specific module itself.
Micro Jump Drive Operation I is required to use any micro jump drives and reduces the spool up time duration by 5% per skill level.