spied in EFI magazine a simple to build, electric powered ducted fan, (E.D.F.), that utilised the easily obtainable Morley Fan unit.
The model was an all balsa, semi-scale Henschel Hs132, (a WW2 early jet dive bomber), with the motor in a pod on top of the fuselage, exhausting between twin fins, not unlike the Heinkel Hel62 Salamander.
A plan was obtained from Traplet (No. MW2575) which showed the model to be easy to construct, giving a wingspan of 47 inches, (1200 mm) and a flying weight of around 3 pounds. Wings were all built-up, sheeted in 1/16 in. balsa, with the fuselage a box of 3/32 in. with triangular corner reinforcement. Fins and tailplane were all 1/8 in. sheet. (Finish was tissue/dope/brushed enamel). The only difficult part proved to be the shroud for the fan. This was carved and sanded by hand from pink foam, finished with a coating of 5P113 resin. I was going to actually buy some foam, but a friend came to the rescue and handed me a piece he retrieved literally from the middle of the road, that had fallen off the back of a lorry. Very cost effective. (It still had the tyre marks on it, slightly squashed but useable). Controls were to be aileron and elevator, with throttle control for the motor. To help keep the weight down, two micro servos were used with a BEG speed controller.
I realised early on from reading many articles on EDF models that weight control was the key for a good performance and this was duly exercised throughout. However, despite my best efforts, the Hs132 ended up quite a bit tail heavy, unforgivable for an electric model, requiring 6 ounces of lead in the nose for a correct CG balance. The short nose, twin fins and motor behind the CG were not working in my favour, coupled with a rearward battery location. Everything was installed as per plan but to my great annoyance the battery was not in the best position, as it sat way back in its own Liteply cradle, designed for easy access and ejection via the cockpit. Before I ripped out the innards to re-position the battery in a more forward location I had a try at flying her, at a flying weight of 3 lb. 8 oz.
The motor fitted to the Morley Fan was a Kyosho Mega, 2 x 18T, initially run on 7 x Sanyo 1700SCR. By suspending the plane by its tail from a spring balance and giving full throttle, the weight increase gave an approximate thrust of 350 gm. A little down on the theoretical 400 gm. available from the Morley.
As expected, all I could achieve was an extended flat powered glide, to belly flop some 50 metres away.
By removing the Liteply cradle and the large lump of lead, I re-positioned the battery fully forward to stand vertically on the floor, up against the nose, wedged in with foam under the canopy hatch. This immediately lost some 5

ounces, though still requiring a little lead using 7 cells. Flying this time proved a bit better, able to fly a low flat circuit but not climb at all.
Next, I removed the 7 cell pack plus nose weight and substituted a pack of elderly 8 x 1800SCR cells, to obtain a perfect balance, giving an all-up weight, as good as it
ever will be of, 3 lb. 21/2 oz. With the eight cell pack the thrust was now approaching 380 gm. And, at the reduced weight, flying should improve a lot.
At last she flew quite well and was able to climb. With very careful handling she could be coaxed to at least tree height, proving very stable and capable of tight turns, though all manoeuvres were, by necessity, of the flat variety. Speed was not great but the low speed handling very impressive and forgiving.
We were now starting to get somewhere with the flying performance and I was starting to get hooked on electric ducted fans and beginning to establish some parameters.
The Kyosho motor is a nice ballraced motor with replaceable brushes, I picked mine up second hand for £10 from a friend. He found it overpowered his model boat somewhat, which spent more time out of the water than in, flying from crest to crest. I am still unsure what the voltage range data for it is. It was not until I read the instruction sheet that I belatedly twigged that I could adjust the timing of the motor. This gave a small improvement to the thrust, now approaching 390 gm. and very close to the theoretical maximum for the Morley Fan. With the fan/motor giving as much thrust as I could coax from it on 8 x 1800SCR Sanyo cells, there was not much more I could do for my all up weight of 3 lb. 21/2 oz.
The flying performance gave an easy hand launch but a non-spectacular climb, so vertical manoeuvres were not possible, due to the low power/weight ratio, more like a powered glider. Duration has been around three to four minutes. However, the Hs-132 has provided me with some valuable data for the future and given me some good incentive to pursue electric ducted fans further. She looks marvellous in the air and has that characteristic whistle sound of the early centrifugal jet engines, especially at part throttle. An anomaly I have found is that the Morley Fan on the Hs-132 performs better at two-thirds throttle than at full, though I am not sure why? The inlet is clear with no long ducts.
As an experiment, and a cost effective one at that, the Henschel Hs 132 has been a success. Although expecting it, I was disappointed at the lack of aerobatic performance but we were limited by the design/fan constraints. I would greatly appreciate any tips from experienced EDF flyers on how to improve the existing setup if possible. Otherwise a more powerful or better suited motor, different fan or more continued