Slow 400 (oz9294)


Slow 400 (oz9294) by Dave Clarkson 1991 - plan thumbnail

About this Plan

Slow 400. Free flght Slow Open Power model. Wing area 401 sq in. For 2.5 to 3.5cc engines.

Quote: "Despite being a committed C/L aero-modeller for almost 25 years, or perhaps because of this, I have always loved F/F power - I lost my first F/F power model long before I built my first Goodyear model.

This love was re-activated when I watched the Open Power flyoff at the 1988 F/F Nationals. Wow! It was like being dose to a battery of anti-aircraft missiles in action. This seemed to me to be mega-modelling requiring every skill - aerodynamics, structures, construction, lightness, big BHP, systems, handling, discipline - and weather. Many of my fellow control-liners have been similarly seduced, and, like them, I decided to have a go at Slow Open Power because it sounded nice and easy. It is not, of course...

I have never built other people's designs but have always used a lot of other people's ideas, so I looked at a lot of old magazines and talked to a lot of F/F power fliers before I started building, flying and learning. First came a little model powered by a Frog 150 - this taught me about aerofoils and trimming. Then there was a big one with a Fuji 35; and I learnt a lot about structures, construction and systems. Both of these were big failures (the Fuji 35 model twice, in public, banging-in close to people - which taught me about safety and prudence). You have to make mistakes to learn - and I sure made some mistakes.

Next came two medium-sized ones, powered by a Silver Swallow 2.47 diesel and an OS Max III.15. These were easy to trim and flew very well but taught me that anti-warp structures are essential, for their trim moved constantly depending upon the weather. The final version is the one presented here and it contains everything I have learned, stolen or copied about Slow Open Power..."

Scan from DBHL, cleanup by theshadow.

ref DBHL-7096.

Direct submission to Outerzone.

Supplementary file notes

Article pages, thanks to Algy2.


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Slow 400 (oz9294) by Dave Clarkson 1991 - model pic

  • (oz9294)
    Slow 400
    by Dave Clarkson
    from Aeromodeller
    September 1991 
    47in span
    IC F/F Pylon
    clean :)
    all formers complete :)
    got article :)
  • Submitted: 01/10/2017
    Filesize: 381KB
    Format: • PDFbitmap
    Credit*: DBHL, theshadow
    Downloads: 602

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