Trial Head Up (mm) Head Down (mm) Change Head (mm) Elapsed Time (min) 3 28 55 27 17.15 2 28 57 29 13.34 4 30 79 49 10.47 5 32 104 72 8.96 6 32 126 94 8.13 7 33 159 126 6.87 8 33 184 151 6.10 1 33 190 157 5.33 0 33 184 151 6.095333333