Today I made a fun experiment. At my club we have two foil sets for pumping:
- a beginner-oriented set with a front wing of 1800 cm² and ~10 AR
- an intermediate-oriented set with a front wing of 1750 and ~13 AR
Each foil set comes with its own stabilizer. The stabilizer for the beginner set has an area of 220 cm², whereas the stabilizer for the intermediate set is much thinner with has an area of 100 cm² and an AR of 13.
I am still a beginner so I mostly tried the beginner set, but today I also tried the intermediate set, just to compare. I felt that it was going faster, was a bit harder to turn, and glided a bit better.
Then I tried to use the intermediate stab (the smaller one) with the beginner front wing. It became very very hard to control on the pitch axis. I felt like if my back foot pressure was slightly offset I was immediately punished.
What I don’t understand is that the same smaller stab on the intermediate front foil did not create that pitch instability. Does anyone know why?