How do I Make a Trebuchet Go 100 Feet in the Air?

Find a safe area to use the trebuchet. This is a vital step. While the goal is to propel an object 100 feet, the fact is, it may go farther. The object may be thrown backward or it may fly straight up and fall to the right or the left of the machine. So choose an area that gives good clearance on all sides.

Add to the counterbalance. More weight on counterbalance means the arm falls faster and gives more power to the missile. Experiment with different weights, but generally the more weight, the farther the missile will go.

Inspect the sling. Many trebuchets are designed so that the length of the sling can be changed. Multiple slings can be made to replace the original sling. In general, the shorter the sling, the higher the missile will fly. This is because a short sling will eject the missile just as the arm reaches its highest point and the missile will continue the upward trajectory. A longer sling will send the missile further because it swings forward as the arm comes to a stop. Experiment with different lengths to find which works best.

Choose the missile. A compact missile will go further than a lightweight missile, because it offers the least wind resistance. Experiment with different weights of missile. Water balloons can be filled with different amounts of water and tied tightly to produce variously weighted missiles. Different-sized raw eggs can also be good test missiles.

Measure the distance of each missile. Measure the distance from the front of the trebuchet to the missile. Keep records of the weight in the counterbalance, the length of the sling and the size of the missile.