Hells Belle (oz1675)
About this Plan
Hells Belle. Free flight gas model. This is a modern redrawn plan in PDFvector format, of the original plan by Vic Smeed. From August 1951 Aeromodeller.
Quote: "Purists, look the other way! Hell's Belle is a strictly functional design in which everything has been sacrificed on the altars of Performance and Durability. With this job, which recognizes no loading or cross-section rules, the fuselage is regarded as merely a means to secure motor, wing and tail in correct relationship, and to provide a little side area here and there. The result is a little short on looks but quite long on flyability, and the Belle's slow, stately flight has a peculiar grace of its own.
Several models, rejoicing in such names as Boozer's Gloom, Flattened Fifth, Dominant Seventh, etc, went into its development; all these jobs incorporated the profile or near-profile fuselage, but variations were made in wing and power loadings, sections, wing and motor positions, etc. Performances were good on the whole, but each model had some vice or other - fragility, tricky trimming, and so on - which rendered it unsuitable for contest work.
Hell's Belle was designed to incorporate all the lessons learned in two seasons with the earlier models, and features such things as low wingloading (under 4 oz per sq ft, or about 2.7 ounces per sq ft of total area), low power-loading (7.5 ounces per cc), ruggedness and easy trimming. The first three flights, carried out on two fairly warm days, produced ratios of approximately 10:1, 18:1 OOS, and 35:1 OOS. The next few flights were in dead air and were devoted to trying to kill the single stall when the motor cut. The only contest success before the close of the 1950 season was flown in a 30 mph wind and steady rain; these conditions tested the model's ability to take punishment rather than its flying capabilities, and it tied for first with an average of a rather poor 5:1. A further series of tests in still air produced an average flight total of 1 min 34 seconds, for an average motor-run of 7 seconds.
The flying speed of the Belle is astonishingly slow, both in the glide and under power, although the climb is a tight, vertical spiral. Trimming is easy, and despite the low all-up weight, the job has shown itself capable of taking rougher handling than the average model. The fuselage is almost indestructible.
Construction is conventional except that only one fuselage frame is required, and that almost the whole model is built from quite soft balsa - soft enough to retain easily the imprint of a finger nail. If a larger motor than the original's Elfin 1.8 is to be used, there is no objection to a slightly harder grade of balsa being employed, although the prototype proved itself adequately strong..."
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by Vic Smeed
all formers complete :)
Found online 14/10/2011 at:
Format: • PDFvector • CADfile
Credit*: rchopper56, hogal
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