ENGINE SIZE?
12-02-2007 | 01:57 AM
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From: new bern,
NC
ENGINE SIZE?
Hi Guys, What engine do you recommend for a Great Planes Pitts 68" span? I"m thinking about a Zenoah 38. I"ve seen several in High Flight mag. with them on the Pitts. I Have a Fuji 50eis on another plane{Reawwind Speedster} What about a DA 50? I feel like a mag. engine like the Zenoah eliminates the need for extra battery. ANY INPUT WILL BE GREATLY APPRECIATED. THANKS. flying viking
12-02-2007 | 02:22 AM
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From: Tampere, FINLAND
RE: ENGINE SIZE?
I am not traditional RC user and in couple years of trials and errors I came to the
following approach:
1. Strenghten the construction with fiber glass; that also changes the position
of the Center of Gravity. That will increase the weight of your plane with about
some 30% and the life about 3x times.
2. See how much weight you need to have in the engine's place and then buy
the engine with the largest displacement & power which has that weight. Beside
too many different opinions, all seems to agree that the Aviation is about the
Power-to-Weight Ratio. Check even the big folks on Reno racers ... no exceptions.
You can always throtle back the excess of power. And power is never enough...
3. Gas makes sense for displacements lot bigger than 26cc, for example for
engine size of at least 50cc and better 80cc. Otherwise the Glow engines are
better choice by many reasons: Power-to-Weight ration, interference, smell,
fire hazard, ... the list is that long so the even the professionals in Giant Scale
convert engines like Zenoah 80cc into glow...
Well, of course all those things are in the assumption that you are going to
spend some years in this hobby... meaning, the modelers tend to migrate
the size of the airplane to a bigger one they build next time, i.e. the engine
too ... But if you are not certain how long you will be in this hobby, then
buy and use Electric power plant ...
following approach:
1. Strenghten the construction with fiber glass; that also changes the position
of the Center of Gravity. That will increase the weight of your plane with about
some 30% and the life about 3x times.
2. See how much weight you need to have in the engine's place and then buy
the engine with the largest displacement & power which has that weight. Beside
too many different opinions, all seems to agree that the Aviation is about the
Power-to-Weight Ratio. Check even the big folks on Reno racers ... no exceptions.
You can always throtle back the excess of power. And power is never enough...
3. Gas makes sense for displacements lot bigger than 26cc, for example for
engine size of at least 50cc and better 80cc. Otherwise the Glow engines are
better choice by many reasons: Power-to-Weight ration, interference, smell,
fire hazard, ... the list is that long so the even the professionals in Giant Scale
convert engines like Zenoah 80cc into glow...
Well, of course all those things are in the assumption that you are going to
spend some years in this hobby... meaning, the modelers tend to migrate
the size of the airplane to a bigger one they build next time, i.e. the engine
too ... But if you are not certain how long you will be in this hobby, then
buy and use Electric power plant ...
