Lambada

 This time I’m ordering VG’s for a friend of mine, who wants them for yet another Sky Ranger. But meantime I changed the plane to Lambada UFM11 with front wheel and fowler flaps – rather fine airplane, than a motorglider although it probably retains finess 24.  I can feather the prop and try to use some thermals. What happens then: you need to turn tight in order not to get out of the lift. The same time you need to keep the speed low in order to reduce the dive. So: I applied VGs on 1/3 of the wing starting from their tips, so that they cover front of ailerons area only. The result: the stall speed without flaps – the one needed for thermal flying – dropped down from 85 to 75 km/h. And the grip in tight turns at low speed seems to be much better. Full flaps landing touch down remains the same: 63 km/h. But I don’t put VGs on all the wing length in order to avoid more nose up landing – the tail in this beauty is long and close to the ground. Anyway: VGs do work again, it’s just a different application.

 

 

Best regards

Piotr, Poland