Couillard

The Couillard was a medieval siege weapon, a type of smaller trebuchet. Instead of a single counter-weight swinging between supports on either side, it has a split counter-weight that passes on either side of a single support.

Its maximum range was about 180 meters, and it could hurl projectiles of about 50 kg. It needed about 8–10 men to achieve a fire rate of 10 projectiles per hour.

Mechanism
The main rod was lowered to attach a sling with the projectile, then the rod was released thus throwing the projectile. A sling was used to add extra speed to the projectile.