Graphs of Lower Surface LE Tape Performance with New Data From 9/29/2012
0 views
Skip to first unread message
j...@oxaero.com
Oct 1, 2012, 1:10:13 PM10/1/12
to Jari Hyvärinen, Deturbulator Participants, Roy Arnold, George Bennett, Nathan Murray
Below are the latest graphs of sink rates and glide ratios for Std. Cirrus #60. Two each measurements for speeds 40, 45, 48, 49, 50, 51, 52, 55 and 60 kts were taken last Saturday. Averaging the 40, 45, 50, 55 and 60 kt points gives three measurements for each speed. 48, 49, 51 and 52 kt speeds are an average of two points. These are plotted, together with a single measurement of speeds 65, 70, 75, 80 and 85 kts from 3/19/2011.
The above named speeds are indicated speeds; whereas, calibrated speeds are plotted, so, for this glider, the points fall to the left of the indicated speeds.
Besides confirming the performance boost for speeds from 45 to 60 kts, the curious thing is the notch at 48 kts indicated back to baseline performance. The reason for taking points 1 kt apart around 50 kts was to look for changes in the top surface boundary profile where a very sharp notch is known to exist between 49 and 51 kts depending on weight change. However, it appears that there is a similar notch associated with a lower surface rear-facing step (rear tape edge).
Jim Hendrix
The above named speeds are indicated speeds; whereas, calibrated speeds are plotted, so, for this glider, the points fall to the left of the indicated speeds.
Besides confirming the performance boost for speeds from 45 to 60 kts, the curious thing is the notch at 48 kts indicated back to baseline performance. The reason for taking points 1 kt apart around 50 kts was to look for changes in the top surface boundary profile where a very sharp notch is known to exist between 49 and 51 kts depending on weight change. However, it appears that there is a similar notch associated with a lower surface rear-facing step (rear tape edge).
Jim Hendrix
Reply all
Reply to author
Forward
0 new messages