Hellbender (oz3413)


Hellbender (oz3413) by M Green 1962 - plan thumbnail

About this Plan

Hellbender. A 64in span FF open power model. From Model Aircraft, February 1962.

Quote: "THIS model is the latest in a series of open designs and was planned originally for a .19 glow motor. It was, in turn, developed from a model having a smaller span and lower weight and using a 2.5 cc diesel. Hellbender should still perform well on a good 2.5 cc motor, particularly if care is taken over the weight and span is reduced by 2 to 4 in. After seeing other .29 jobs perform, I decided to fit an Eta 29, the results being well justified.

These highly powered models are more tricky than their 2.5 counterparts, but not exceptionally so. More care is needed during the initial stages and adjustments tend to be finer, but once trimmed you really have got something!

Construction. Fuselage. The only feature a little out of the ordinary is the method of fixing the engine bearers, which was devised to take into account the rear intake on the Eta 29. Remember to glue the bearers to the ply plate with Araldite or a similar glue - not balsa cement. Apart from this the construction of the basic fuselage and pylon is self explanatory, but care must be exercised to keep things straight.

Tank and Timer. A tank of some 30 cc capacity is needed for a .29, so if you dislike soldering, I suggest using a team race tank. Some thought should be given to the tank installation etc before the fuselage construction gets too far advanced, as precise details inevitably depend on the motor used. Needless to say, the timer must be too per cent. accurate, capable of cutting the motor consistently at the desired time.

Wing. Use good quality wood of the correct grade. Pin down LE and TE, and glue or cement in the ribs. Do not forget to pack up the front of the TE by 1/32 in to give the correct droop - likewise the wash-in on the right inner panel. The tip ribs are rather a wangle, but ultimately work out OK. Cut the notches for the spars. Assemble the whole wing, taking care over dihedral angles. When set - not before - cement the spars and remaining dihedral braces in place and then sheet cover the LE..."

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Hellbender (oz3413) by M Green 1962 - model pic


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