Part of the plan of this dual personality Big Tire Cruzer is enhancing the short field and STOL capability of the aircraft. The wheels, tires and brakes help out, and the 80″ prop I am getting setup to install will help it hop off the ground, but for STOL landings and for really steep climbs you need more slow speed capability for the Cruzer.
STOLSpeed has a very nice affordable set of Vortex Generators that when installed properly can nearly the same stall speeds as the STOL and significantly improve handling characteristics in the slow speed regime.
The are installed on the Cruzer at about 4.2 inches back from the wing tip. About midway from the 3rd and 4th rib rivets. The little wings bend the air to cause it to swirl around itself and this vortex it generates (thus the name) helps keep the air from separating when in stall. It will delay stalls significantly vs. a wing without them.
I used the included templates to set 15 VG’s at a 60 mm pitch and then another 30 at a 90 mm pitch. After getting the main wing setup I went for a test flight.
I started with a clean stall at it was clear that the stall speed was lower and the control was much better.
Next was a full flaps stall and that also was much improved. Really there is no stall at all as long as you keep the balls centered. Just some buffet and a 3-500FPM decent, but no break at all.
After that I used some power to get a super high-alpha stall. I saw speeds dip into the 20’s.
Next was the departure stalls.I slowed to rotation speed and then hit the power while pulling the stick back all the way. Surprisingly there was never any stall. I had to increase right rudder until it was on the stop because of the high Alpha p-factor. No matter what I tired it just kept climbing while the power was in and if I kept the ball centered I could do whatever I wanted.
Stalls where easy before, now they were wicket amazing.