RC2062 Slingsby T31M

Name: Slingsby T31M
Model type: Scale motor glider
Designed by: Peter Miller
Wingspan: 86”
Fuselage length: 47”
Wing area: 682 sq. in.
All-up weight: 5 lbs
Wing loading: 17oz / sq. ft.
Functions (servos): Aileron (2); elevator (1); rudder (1); throttle (1)
Rec’d engine: .40cu. in. four-stroke

Originally featured in the March 2010 issue of RCM&E

Back in 1947, Slingsby Sailplanes produced a single-seat powered aircraft by hanging the wings and tail of the pre-war T8 Kirby Tutor (or Cadet Mk.II as the RAF called it) on a new fuselage with either a JAP or Scott engine up front. The result was the T29 Kirby Motor Tutor. You don’t remember it? No, well there’s no reason why you should, really: the Kirby Motor Tutor was a rather half-cocked bid for a share of the power training market. It did fl y, but the little ultralight scarcely made it over the hedge of the CAA’s certification process before settling heavily back to earth with no prospect of ever going into production.

Putting this sorry episode behind them, Fred Slingsby and his factory got on with better things - things like the Slingsby T31 Tandem Tutor, or the Cadet Mk.III as you’ll remember it if PETER MILLER MODELS AN UNUSUAL BUT ODDLY ALLURING PHOENIX you learned to fl y with the Air Training Corps. Given Slingsby’s post-war successes, the T29 might have remained a forgotten family

embarrassment - Fred apparently described it as a “foolish and wasteful venture” - if it hadn’t been for the fact that, when the RAF sold off its T31s in the 1980s, home-builders remarked on the similarity of these trainers to the old T29 Motor Tutor, and set about fitting undercarriages and bolting in engines where the front cockpit used to be. All this effort turned the stolid sailplanes into T31M Motor Cadet IIIs whose configurations display all sorts of variations but which share one important common denominator: they all offer large measures of low-cost flying fun. 

So much for full-size history, then; what’s the background to this model? Well, several years ago I built a 73” span electric-powered T31M for an acquaintance who flew gliders and vintage models but wanted something a little more advanced. It was a lovely model to fl y and inspired me to build one for myself around an old pre-Surpass O.S. FS40. I based my model on G-BSHM (now PH1121) because I liked the look of the angular front deck and its colour scheme. The result is a model that’s accurate in most respects, save for a couple of omissions: I wasn’t sure whether ‘HM has the spoilers that are fitted to some T31Ms, so I didn’t put any on the model - which makes the build easier, of course - and the cowl has been simplified slightly by omitting the bump that hides the self-starter.

 Building the model is quite straightforward - very much like a vintage design, in fact - indeed the only area that calls for care and great accuracy is the strut assembly and wing mounting, but we’ll come to that in the fullness of time.