A Retro Glider Project
Wizard of Oz
The Wizard-of-Oz is a single channel slope soarer designed by James H. Osbourne. It was featured in the April 1966 edition of Aeromodeller and is described as "a 4ft simple glider for radio controlled soaring".
It features a thick undercambered wing section, tailplane of built-up construction and a sheeted fuselage resulting in a rather "boxy" looking model. However, I think that it has a certain charm and character all of its own. Even so the airframe was relatively advanced for its time, being one of the first "compact" type models specifically designed for slope soaring.
The original shows an Elmic Conquest escapement with a RCS receiver. The plan was available from the Aeromodeller Plans Service and it might still be available from X-list plans: http://www.xlistplans.demon.co.uk/
I found my copy of the plan while clearing out my house. I bought this over 25 years ago as a teenager, but never got around to constructing it. I now decided to build the model as a way of getting myself back into R/C aero-modelling (I have not flown for years) and to make it a bit more interesting I decided to make it as per original, i.e. single channel, using radio equipment of the period. For obvious reasons the receiver had to be superhet and getting hold of suitable working radio control took months of searching and research.
Views of completed model.
Details of my version are:
Airframe Details
- Built-up wing & tailplane.
- Sheet fin and slab sided sheet fuselage.
- Wing span: 48in (1219mm)
- Wing area: 360sq.in (23.2sq.dm)
- Length: 37.7/8in (962mm)
- Total flying weight: 1lb.10oz (737g)
- Wing loading: 10oz/sq.in (32g/sq.dm)
- Fuselage covering: traditional nylon - great stuff
- Wing, tailplane & fin covering: Vintage SolarTex
Radio Equipment
- Elmic Compact escapement (rubber driven of course) for rudder only control
- MacGregor MR60 single channel superhet receiver
- MacGregor PowerMac transmitter.
Most of this was purchased from eBay.
All worked out within the weight range specified on the plan (1.1/2 to 1.3/4lb) and the finished model is certainly very strong. I would have finished the entire airframe in nylon if I could get hold of this material in a light enough weight. The nylon available today is significantly heavier than the small amount that I still had left from the mid-1970s! Still waiting to fly it on a quiet Dorset hill side, although I have conducted some trimming test glides. Will let you know how it goes.
Peter Studzinski Email: P.A.Studzinski at soton dot ac dot uk