38" and 70" sports wing

soaring Maiden Castle, Dorset

This 38" tapered wing was my first successful wing. It performed in a range of conditions and was a very 'parcel shelf' handy size. The model had micro radio gear and a 110mah nimh battery. I'm guessing the all up weight was around 8 or 9oz, and the wing section was an MH45. I cut the cores from white foam and skinned them in 1/32nd balsa, with a final film cover.

38" wing

It thermalled well (inverted at times!) and could handle a decent blow. The wing would loop and do a roll (even if it was a bit barrelly). I pushed the cg further and further back until I got to a point where it had a nasty, snappy stall (I first thought it was radio trouble) that would strike with full aileron deflection.

The model was flown nearly to death (it languishes in my shed, splintered and crumbling) but inspired me to build a 70" span version. This larger wing showed promise, but sported several 'improvements' that meant its full potential was never realised.

70" wing

I decided to cut less washout into this wing (bad idea) on the basis this was going to be a speed machine who needed all that drag? I also chopped out teeny tiny elevons to combat the snake bite stall (really bad idea). I ended up with a model that would only successfully launch 50% of the time, would haul round the sky at some speed, yet would take all week to respond to aileron input. It did carry the energy really well though, and its forte was any maneuver where modest control inputs were required. This boiled down to cruising around at 'safety' altitude, or doing large slope edge pumps. Landings were best tackled in a 10 acre grassy field clear of other persons.

This was also a foam cored wing, but skinned in ply and glassed.

this era of wing building also spawned a non tapered version of the 38" wing in an attempt to get away from the Zagi like appearance, it was in fact a 40" span skinned in 1/64th ply and brown paper, flew much like the 38" original but without the low wind performance

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