Shark (oz8973)

About this Plan

Shark. Sport flying boat model for .20 -.25 engines. Wingspan 50in.

Quote: "If you fancy joining your water based counparts, the Shark could be an ideal first model. Built for .20 - 25 engines. Designer Stephen Lough show you the way.

This flying boat was built after my first visit to Keilder Water where I was flying sports models fitted with floats. Whilst looking around the models present, I realised there were very few flying boats and those that were there were not particularly successful.

On returning home, I got pencil and paper and started reading about hull design. Eventually this resulted in a quarter scale sketch of the model presented here.

First attempts at ROW with tip floats made from block balsa were unsuccessful since they were too small. On that occasion, I removed the tip floats and had the machine hand launched by a friend. It did fly but at the expense of full up trim! Back home I increased the engine up-thrust from two degrees to five degrees and made larger tip floats from foam as shown on the plan. The next flight was a very different story. Taxiing was no problem - even cross wind - and she was planing on the step within a couple of feet.

I have taken off in every conceivable direction in relation to the wind including a down wind take off at Keilder Water in a 10-15 mph wind. Although the run was a bit long-winded(!) she came unstuck with no problem.

Construction: Use waterproof or water resistant glue throughout!

Fuselage, fin and tailplane. This is a simple balsa box construction using medium 1/8 inch balsa sides cut as shown. All formers, including the 1/8 inch ply ones should be cut as shown. Join the fuselage sides together using F4 and F5 (these being of equal width) using epoxy. The back end can now be pulled together and glued. F2 and F3 are pinned in place without glue and F1 is then epoxied in. It might be necessary to dampen the wood to get it to bend with equal curvature on both sides. Add all other formers when dry. Next add the bottom 1/16 inch hard sheet (cross grained), glue the 1/4 inch sheet keel formers on the centre line..."

Shark, R/C Model World, August 1989.

Direct submission to Outerzone.

Supplementary file notes

Article pages, thanks to RFJ.

Corrections?

Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction