The Rapid Fire is a weapon mod that appears in Titanfall for the Quad Rocket. This modifies the weapon so that it fires one rocket at a time, and converts it to automatic fire. It holds 18 rockets in a clip and has four times the fire rate, up from 78 RPM to 312 RPM. The recoil of the quad rocket is decreased, obviously because less rockets are fired per shot. The unmodded Quad Rocket fires 4 rockets at once with .77 seconds between shot, with the Rapid Fire firing 1 rocket with .19 seconds between each shot; the Rapid fire Quad Rocket can fire 4 rockets starting from when the Factory default fired its first shot to right when the Factory default fires it's next 4 rockets.
The drawback is reduced damage, which somewhat negates one of the great strengths of the Quad Rocket, it's damage. The ability to rapid-fire with increased accuracy is justifiable to some pilots, while others say the Extended Magazine is more useful, as it allows more full-damage rockets to be fired in the traditional fashion. It is a matter of skill and personal preference to which version is better.
In the game mode Frontier Defense, Mortar Titans use the Quad Rocket with the Rapid fire mod in an artillery mode, firing the rockets into the air to come down on the Harvester from great distances. Only the mortar Titan is capable of doing this.