skywagon8a
MEMBER
SE Mass MA6
As I mentioned in post #52, previously I had seen a minimum GPS speed of 28 mph. I can't explain that number as today I proved it wrong. Today is high overcast with zero to 1 mph of wind. Glassy water everywhere and smooth air. I was able to determine that minimum speed in ground/water effect was 30 mph IAS and 41 mph on the GPS. Flown in opposite directions with the numbers being the same in both directions. This was with power enough to keep it in the air. The elevator at minimum speeds is very touchy. With proper control inputs I was able to lift off the water at 30 mph IAS with 56 degrees of flap. When I attempted to pull it off at a slower speed, the water drag increased enough to extend the run holding the Cub on the water until 33 or 34 mph IAS. The next time I get this same weather opportunity, I'll try lifting out one float to reduce the take off speed. I didn't think of that today.
Another thing I noticed during test #6 was there was just a touch of right wing heaviness. I attributed that to not having full fuel. Today with full fuel, it was still there but only at the new higher cruise speed. The wing now flies very slightly nose down in cruise, perhaps only 1 degree difference than before. Perhaps there is a slight shape difference somewhere which causes this? The ailerons were displaced by about 1/16" to 3/32" to correct the heaviness. When I reduce the power to 2300 rpm the heaviness became minimized and the ailerons were streamlined.
Another thing I noticed during test #6 was there was just a touch of right wing heaviness. I attributed that to not having full fuel. Today with full fuel, it was still there but only at the new higher cruise speed. The wing now flies very slightly nose down in cruise, perhaps only 1 degree difference than before. Perhaps there is a slight shape difference somewhere which causes this? The ailerons were displaced by about 1/16" to 3/32" to correct the heaviness. When I reduce the power to 2300 rpm the heaviness became minimized and the ailerons were streamlined.