Roger's 25% scale Supermarine Sea Otter was completed in March 2000. This page shows some pictures of the model and details of its construction.

The manufacture of the full-size Sea Otter began in 1940. It was designed to replace the Walrus for navel spotting and reconnaissance duties. The Mark II was later used for air/sea rescue missions. It entered operational service late in the war with the first navel squadron formed in 1944. There was a crew of three and armament  consisted of .303" Vickers machine guns. Bombs and depth charges could be carried, one under each lower wing.  

The model was scaled up from a 47" Traplet plan. Roger modified the plans and then had them photocopied up to quarter scale. This produced a 12" diameter cowl, large enough to hide the twin cylinder engine he wanted to use. A lot of details and three view drawings were provided by the Flight Air Arm Museum archive department in Yeovilton.

The model is built-up apart from the wings which are foam, supplied by Pat Teikle. Bracing wire and fittings were supplied by Mick Reeves. 

For ease of transport the fuselage is split just behind the cockpit. The wings are removed from the body as two components with the rigging complete.  This makes assembly quick and easy.

Cowl, floats, wing tips and other small parts were made from GRP to keep things light.  The elevator and rudder are tissue covered for the same reason. 

The aim throughout the project was to keep the structure simple and hence I decided not to bother with a retractable undercarriage

The engine is inverted so that the exhaust outlet is at the top of the engine pod as per the full-size.

AH designs provided the crew.

The radio and batteries are in the nose section. It has two pounds of lead next to the batteries to balance the model.

The radio is Futaba gear with HiTec servos. SM Services provided an opto-isolated board so that the servos could be run off 6V with the receiver at 4.8V. This ensures adequate voltages are provided to the servos by reducing the effect of voltage drops in the long lengths of wire.

Test flights began in March 2000. The plane has proven very easy to fly and is regularly seen at LMA shows.

The specification of the model is:

• Scale: 25%
• Wingspan: 10 ft
• Engine: Zenoah 74cc twin
• Weight: just under 40lb

Roger's Sea Otter (Catton Hall 2001)

In flight.

Roger with his Otter.

This page was last updated on 25/1/03.

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