I just got done ferrying a cub with Keller Flaps and Slats. I have never flown a plane with either flaps or slats. My comparison are squared off wings and stock wings, so please understand my experience with the mods is limited.
First thing I noticed was the feel of the flaps at the handle was slightly different. No big deal, but just an interesting aside.
The plane flies incredibly slow, lands short and takes off in almost nothing. We had a whole six or eight knots of wind, and with 30 gallons of fuel and me, hundred pounds of gear in the plane I was off in 100' or less. Landing is about 150' without heavy breaking or trying to drop it in in a stall.
I finally got comfortable enough that I could look at the airspeed. I was on final at 30 mph. The plane was flying well, but at that speed the controls are mushy- wishing for deeper chord ailerons for sure. A little puff of wind, 3 KTS even, and the plane would balloon 10' in the air- but it never wanted to stall out or quit flying.
The trim really needs to be limber, as you slow down you need to keep rolling forward trim in, lots of trip.
My touchdowns were gentle and docile. It never felt like I had pushed the wing over the edge to a stall. I think I was down to 25 mph and she just stayed flying.
I got eight take offs and landings in the plane. The last one I got to go out totally light with lower fuel, (180 lbs), and that was the chance I could measure take-off distance. The previous take offs were longer, but had heavy fuel, never did it feel like I was using lots of runway.
My airspeed suffered with the mods this plane had. She was slow as a J-3. That said, if I wanted to go into little bitty places with a cub, I would be investing in slats and Keller flaps!!
After a night's sleep I remembered some other things to mention: First let the plane slow down before putting on the flaps, lots of stress on the wing with that much flap hanging down... I waited until under 60, and tried for under 50. Leave the last notch until short final- when ever I pulled the last notch the plane would tend to drift left, this was especially apparent on take off. With the amount of lift that wing was producing, and the very slow speed, all the left forces just sucked the plane sideways- not a quick turn the Maule will do to me. Takes lots of right rudder, and I mean way more than I am used to.
Again, none of it was bad, but just different, and worth practicing before you depart for a super short narrow place.
