Ken's sketch is shown on the left. My variation (on the right) relies on a bit of tension in the strut pairs to keep the ends in place. The tubes are 18swg alloy and are secured to the ribs with tape.

With the strut attachment method decided and the motor wiring threaded through the wing, the leading edge portions of the lower wing centre and inner panels were sheeted and the undersides of the nacelles built up, culminating in those very characteristic undercarriage trousers, which were made from 0.4mm plywood.

Firewall position needed to be determined at this time too, which of course meant deciding on the motors. . .

The first motors I bought turned out to be a bit too 'hot' for this application and were really not happy on anything larger than an 8in diameter prop. I then found these Keda KD 2217-20T motors for sale very cheaply which are apparently also available under the Turnigy label. A quick test with a 10 x 7 propeller borrowed from the Sealand gave 7,700rpm for a current draw of just over 15amps off a 3s 3700mah LiPo pack. Spot on.

The case-mounted prop drivers are very neat but leave very little space between the front of the case and the propeller, so cowl building called for some care. There was also the issue of motor cooling to consider - always a potential problem with a cowled and spinnered installation.

The cowl front was built up of laminations. The middle lamination was cut away to form a duct, directing air up into the cooling slots around the front periphery of the motor case.

The picture on the right shows a completed nacelle, with motor cowl and u/c trouser. It also shows that the spinner (also borrowed from the Sealand) is entirely the wrong shape!

The cowl is retained by a single screw into a threaded hexagonal tube - salvaged from a crashed helicopter!

The end of April was marked by the first sunny spell of the year, so it was out onto the grass for some more pictures.

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