Auto-rotators

Kids entered a friendly auto-rotator (paper helicopter) competition. The challenge was to design, build, analyze, and drop an auto-rotator that would have the slowest rate of descent (stay in the air the longest). Time would start when the auto-rotator would break the plane of two meter sticks hanging from the ceiling, 91.5 inches above the floor.

Above, kids are designing and creating prototypes.

Close up of Emily and Elly working (Emily came in 2nd place in the competition).

Kids had a chance to test drop their official auto-rotators before the competition.

Above is a blueprint of an auto-rotator. The measurements shown would be used by kids to determine how aerodynamic their auto-rotators were. Kids used formulas for wingspan and wing area to calculate the aspect ratio of the propellers. Kids also used formulas for area and weight to calculate wing loading. Finally, kids used a math model to estimate the rate of descent and flight time of their auto-rotators to predict their performance in the competition (a time of 3 seconds or more is considered good).

Julie came in 3rd in the competition (Megan Peacock came in first).