After many years of procrastinating I'm finally building a Phase 5. Designed in 1978 this model is often considered to be Chris Foss's (CF) best slope model. It was never available as a kit so the only way to get one is to build it yourself. CF is still selling the plans if you fancy one.

The Phase 5 plan calls for a built up wing but I'm deviating from the plan and making one from foam with a balsa skin. A snow day today meant I could make a start. CF does not specify what sections are used for the root or the tip so a bit of guesswork and internet trawling resulted in the semi-symmetrical E374 for the root, modified a little to make it thinner. The tip is fully symmetrical and is between NACA 0010 and 0011. It's actually 10.67% thick so maybe it's NACA 0010.67?

My 5 year old Super Chipmunk "Pennzoil" from Apache Aviation now supplied by SLEC had always had an ASP180FS up front.  Beautiful sound but I now feel that the model really needed something more substantial power wise.  The ASP180 should be producing around 2.6 hp when tweaked and tuned and I have to say I have tried many props on this motor and never felt really happy.  Plus the fact that the glow fuel residue inside the cowl would slowly weep out and eat the "so called" fuel proof paint on the cowl.  But what could I replace it with. DLE30 or DLE35RA or OS GT33?  After much deliberation I went for the OS GT33.  Coing close to four horse power from this tidy gas engine.  However, the conversion to petrol was not as simple as imagined!