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Bell 47 H-1 |
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Feasibility study |
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Finding a 3 dimensional plan is important when scratch building to establish key aspect ratios. In this case a plan was scanned into a computer to be enlarged accordingly. |
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The plan was enlarged so that when printed the main rotor diameter was equivalent to 1,220mm. This was suitable for a 30 class two stroke model engine; this smaller size was chosen in an attempt to contain development costs. A ‘square cut’ carbon blade is shown in the picture to be an exact match. Modern model blades often have a swept tip for enhanced aerodynamics. In this case a longer blade was cut down for added scale appeal. |
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Having established the size of the model the next step was to select an appropriate set of mechanics. To do this card profiles were cut to shape. |
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These shapes were then compared with several sets
of commercially available side frames. However, none were available due to
the particular profile of this model. The picture shows a comparison with the
Hirobo 30 size scale mechanics that are about 5 cm too high. Having assessed whether or not the project was viable it was decided that a new custom set of side frames would be required. |
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Webmaster: John Neasham |
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