Storm the Castle
| Information | Rules | Competition | Scoring | Pictures | Past Scores |


Storm the Castle is an event involving a device that can only take up a limited amount of space which must fire a projectile. Distance and accuracy determine your score. This event can also be reffered to as Trebuchet, as most teams build Trebuchets as their device.


  • The device mut fit inside a box that is 75 cm high, 75 cm wide, and 100 cm long (measured parallel to the direction of the launch)
  • It must operate within a 2-meter by 2-meter square launch area
  • It can only be triggered from outside the launch area
  • The counterweight will be given to the team during competition. It will be between 1 to 3 Kg and will have a hook on top
  • The counterweight an hook will fit within a 15cm cube
  • The hook will fit through a 9mm hole or eye screw. The hole cannot be more than 7cm thick, and not more than 1 cm from the edge of the material (i.e. the arm)
  • Neither the counterweight or projectiles can be modified.
  • The masses of the counterweight and projectiles will not be announced until after impounding.
  • The device, without counterweights, cannot contribute energy to the launch. (i.e. with no weights on the arm, it should balance)
  • The center of gravity cannot drop during the launch
  • The triggering mechanism cannot contribute energy to the launch
  • You must wear goggles when launching.



  • Bring everything you need when you come
  • You need to give warning prior to each launch. Some teams might chose to yell something strange, or you can just say 'Firing!'
  • The target will be at least 20 cm high and wide, which the team will set at the distance they desire
  • At competition time, the team will take their device to the launch area, along with any materials they brought.
  • No outside help is allowed. So tell Mr. Krieger to be quiet.
  • Teams have 5 minutes to make 3 launch attempts
  • If the device does not go through the launch motion, it is not considered a launch attempt
  • Any modifications, using the tools brought by the team, can be made during the five minutes



  • The score is determined by distance and accuracy.
  • The DISTANCE score (D) will be the distance from the midmpoint of the dront line to the projectiles first point of impact.
  • The ACCURACY score (A) will be equal to the distance from the point of impat to the center of the target.
  • A BONUS score (B) of 0.10 times the disance score will be added if the target is hit
  • Launch Score= D-2A + B
  • Graph Score= A team may bring graphs to help them launch. Copies of these graphs should be given to the judges for extra points. Up to 2 points per graph may be awarded with a maximum of ten points
  • FINAL SCORE= 2 Best Launch Scores + Graph Score - Penalties
Launch #
Requested Target Distance
Distance (D)
Accuracy (A)
Hit? (check if yes)
Bonus (B)
(D x 0.1)
Launch Score




Past Scores

Meet Rank
WSSL 05-06 4th
Olympiad 2006 3rd
WSSL 04-05 9th