WEAPONS: Engineering - Multi Cannon - #00043
On the first glimpse, the multi cannon is just an ancient-gatling-gone-to-space kind of thing with boring kinetic damage and without any 'coolness' factor.
On a second glimpse, it is one of the most capable weapons in Elite Dangerous. Read here about what your engineers can do to turn a viable tool into a devastating weapon.
Multi Cannons are basically 19th-century-machine guns. They use projectiles with limited ammo and a high projectile speed. Nonetheless, they need to lead their target's movement.
Most cmdrs intuitively position themselves in a way that leads to the enemy going upward in forward view. If you're one of these, please consider that the above described 'lead' on the target makes it impossible for a multi cannon to shoot at a target that is in the upper half of your windscreen.
Basically, you should try to mount multi cannons on the upper side of your ship and weapons with (near) infinite projectile speed on your ship's belly.
Multi cannons come in a fixed version without aiming, gimballed version with forward aiming on sight and turreted aiming which basically targets everything that's in the weapon's view.
Turret versions are good for multi cannons that are largely used for an experimental effect (read below), like 'emissive' to light up a silent running or low temperature ship. They're the weakest version but as effective on damage-per-energy as fixed weapons.
Gimballed versions are fine alrounders which find their use in PvE and on bigger ships in PvP (Aiming with fixed multi cannons is problematic the moment you switch your Cobra Mk III for a small moon). They're about 50% stronger than turret versions, but only about half as effective in turning energy to damage.
Fixed versions are the strongest and most effective. Their damage potential per second is about 100% higher than turret versions with the same superior efficiency as turret versions.
In short: Flying a big ship that doesn't move well? You might consider turreted versions. Same if your multi cannon is only for 'marking' an enemy in some way. Need an alrounder? Get a gimballed version. You're hardcore? Get a fixed version. Most punch. Highest efficiency.
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