Each run of the experiment consisted of one of the group members standing on a chair beneath a string suspended from the ceiling to a point 100 inches above the floor. While holding the helicopter with the bottom of its base at the 100 inch height, that group member (the ``releaser'') released the helicopter. At the release, a second group member (the ``timer'') began timing the fall using a stopwatch. Timing was stopped as soon as any part of the helicopter touched the floor. The third group member recorded the time, which was expressed in hundredths of a second above two seconds (all times were in excess of two seconds). So, for example, a time of 23 means 2.23 seconds.
Each of the three group members took turns releasing and timing. This was done in a random order (we used SAS/INSIGHT to generate the random numbers used to determine the order). Each releaser-timer combination conducted ten drops, resulting in a total of 60 data values.
Figure 1: Pattern for Making the Helicopter
Table 1: Plotting Symbols for Groups
Figure 2: Helicopter Data: Scatterplot of Time versus Order
Figure 3: Helicopter Data: Scatterplot of Time versus Group