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Late last summer, I
started planning for a run to make the 2003 F3C World Heli Team during
the 2002 flying season. In thinking about this attempt, I began to think
about the pros and cons to flying a Pod and Boom model, vs. a Fuselage
(fully enclosed) model.
The benefits to the
fuselage were that the model has a much more pleasing appearance and
presentation, the downside is that it is more affected by wind, etc in a
hover, and is also more prone to damage in the event of a boom strike
while stretching an auto. The Pod and Boom on the other hand does not
suffer from the problems of a fuselage, but it does not have as much of a
presence during aerobatics. Pod and Boom models also tend to have more
drag due to turbulence from the back of the canopy, which affects forward
speed and the size of the maneuvers.
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Since both types of models
each had benefits, I then began to think about trying to take the
benefits of the Pod and Boom (simplicity, hovers well in the wind), and
combine this with the benefits of the fuselage (Speed and presentation).
I then remembered a model called the "Baron 60 EX "
manufactured by Kalt in the mid 80's that had a unique rear section that
attached to the front of the canopy to form a full cover or Pod over the
mechanics. While this was never a very popular model, I decided that I
could use this idea, and hopefully achieve the results I was looking for.
It made sense: The rear section would reduce the turbulent air at the
back of the canopy, while preventing the air from being trapped in the
front of the canopy while hovering downwind. The reduced turbulence would
also increase the forward speed, allowing for larger aerobatics. By
keeping the body profile tight fitting to the frames, the side profile
would not be increased (this causes the model to be pushed around while
hovering in the wind). The enclosed look would also improve the
presentation of the model, and possibly also reduce the noise level of
the mechanics.
I then made a sketch of
what the Eclipse would look like, and got to work. I started making the
plug for the Eclipse by using a standard Vigor CS canopy, and then
grafting blue insulation foam to extend the canopy and achieve the
desired shape. After much measuring, sanding and filling, and coating
with epoxy resin, the Eclipse (named because it covers the entire
mechanics) finally took shape.
I then sent the Plug
out to my friend Steve at Aeroglass, and he made the mold and the final
bodies. I finished up the first JR Vigor CS bodies Eclipse just before
the 2002 Toledo show (finished 3rd). The original model had very little
in the way of air openings, which proved to cause some temperature issues
on initial flights. These cooling issues prompted me to put the Eclipse
project on hold until after the US Nationals, as I needed to use the time
for practicing since this would be ½ of my score for the US team
selection.
Once the Nats were
over, I then started to enlarge the side window openings to improve the
airflow. I also added some small "NASA" style openings at the
front of each cheek to aid in clean air flow over the muffler. With these
changes, the Eclipse now flies as I had hoped. The forward speed has
increased over the standard canopy. The model hovers well in varying wind
conditions, and the presentation and appearance of the model is also
greatly improved.
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