Bill Manning was their aircraft designer from 1908 to 1926. He attended the Itford meeting in October 1922, as a Royal Aero Club observer and recognized the low drag being achieved. If he could apply this to a powered aircraft...... He went back to draw a monoplane with a thick cantilever wing, and a 398 cc flat twin ABC motor bike engine, quoted to give 7.25 hp at 4500 rpm, but the 3.75 feet diameter prop only reached 2,700 rpm. Wing span 37 feet, chord 3-5 feet. Equipped weight 232 lb., all-up 360 (designed to be 210 + pilot 140 + petrol & oil 10) Top speed 45 knots. Climb rate 200 fpm.
In our terms a self-sustaining motor glider, but with a very low Rough Air Speed. The structure was very lightly built, before skins were expected to take any loads. Internal wire bracing held the structure together, because glues were not trusted, and provided the stiffness. External wire bracing was avoided. The Scheibe Motor Falke is the nearest (two-seat) modern equivalent.
Anyway the Wren attracted an Air Ministry contract as a light trainer for the RAF, and the first low hops were made at Ashton Park ( just north of Preston Dock ) in April 1923, then it was taken to Lytham and flown from the beach. Cookson's bakery uses the original hangars of the English Electric flying boat base. It flew for 68 minutes one day on less than one gallon ! Also landed in a field once, when it couldn't get back home.
The Daily Mail ran another contest at Lympne (Kent) airfield in October 1923, for the longest flight on a single gallon. The dry tank was given just that, then the aircraft was flown round a 15 mile triangular course until the engine started to cough. The Wren tied for first place on 87.5 miles. However the thing wasn't really practical, and never caught on, but one survived to be restored and flown at Warton in 1956. The weight had grown to 266 lbs, they made a larger coarser prop. and climbed to 1200 feet once they had coaxed the motor up to 2,500 revs. Beamont achieved level flight between 30 and 35 knots only, and could barely climb at all. He praised the handling, but regretted the lack of power. The Wren went to Shuttleworth where it is kept airworthy, and it was overhauled again at Warton in 1981.