Monday 20 August 2018

Projects

Phase 5 by Chris Foss

Phase 5 Maiden Flight

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?

The Flying Dolphin

Once upon a time in a galaxy far, far away, well planet earth any way, back at the Nationals of distant past. Jon Tappin and I used to compete against a man called John Dodd in F3A.  We were absolutely amazed that in the evening he brought out a flying dolphin which was free flight. This little thing was so stable, more stable than me that is for certain; it always stayed in our minds.

PC21 50e Vario Prop

pc21

This is an assembly and customisation article of this popular and sleek military trainer from Sebart.  The model comes in three variations of colours.  The model featured is the third generation, version 3 which has all metal retracts.  The earlier versions were plastic and caused many pilots grief, modifications were mad eon theMKII but many swapped out their retracts for E-flite trike sets with anti-jam feature adding around £120 to the cost of the model. Sebart's third genration has all metal retractsand uses a sequencer circuit to operate the gear. On the sequencer there are two spare pins which  can be used for other items that need to be switched when the gear is triggered. Landing lights?

 However, in this article I am upping the scale looks with a super looking prop just like it's full size counterpart and some customisation.  Some info on the real beast first.

Super Chipmunk Engine Swap

Art Scholl Chipmunk

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!