For a number of reasons which will become evident over the next several weeks, I have started to do performance testing on the airplane.
My initial plan was to fly a performance test flight then make a change and then fly the performance test flight again and compare. It turns out there are just too many variables for that simple method.
Fortunately, there are non-profesional racers in the world who do this type of stuff all the time. They have been invaluable. The above image and description is based on their years of experience.
What is important to note is that the procedure strives to eliminate some variables, adjust for others, and mitigate still others.
The actual application of the procedure is a bit less precise than the description of the procedure. Here is an example:
I ran the above procedure three consecutive times in a single flight and yet the NTPS spreadsheet (National Test Pilots School) calculations yielded 157.8kts, 158.9kts and 160.1kts respectively. My hypothesis is that ground terrain was one factor I had not considered. The combination of trees, reflective poly covered tomato fields, and muddy inlets results in varrying amounts of thermal activity. The last of those three tests was performed completely over water and thereby significantly reducing the variability.
I plan to fly the test procedure over a couple more days in hopes to see the results stabilize. Once I have a trusted baseline, I can make the first change to the airplane.
It may all sound a bit boring but I'm actually finding the process to be enjoyable.
Don't expect to see me out on the race circuit as a result of this work. The airplane is an economy flier, not a speed daemon.