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Plan: Midge
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MODELS > Plans: Jetex 50 > Midge

 Midge

by Bill Dean

Reprinted from RAF Flying Review, February 1955, p. 37

Just 2-3 hours building time is all you need to get this ¹/12 scale Folland fighter airborne

Dean's Midge
Dean's Midge

THIS MONTH’S model is a scale replica of one of the most beautiful British fighters now flying—the fascinating new private venture Folland Midge. As with the other “flying scales” in this series (Swift and Skyray), power is supplied by a ¼ ounce Jetex 50 motor and the building plans are shown full size. However, this latest design has the best performance of the three, since a cambered type wing is featured and a catapult launching method enables altitude to be gained—while the jet-thrust is actually building up.

Construction is quite straightforward, but for those who are new to model building, we shall cover the various stages in detail. Start by carefully selecting good quality ¹/16 in. and ¹/8 in. sheet balsa of the grade specified on the plan. Trace the parts (A to F) on to the sheet—ascertaining that the grain direction is the same as indicated. After cutting out the parts (make two wing panels), sand them perfectly smooth with garnet paper.

The Fuselage
 

Two ways to get the Midge plan:
Easy, but smaller
Print this page. At the bottom, and fitting within the page width, is a dimensioned copy of the plan, set to print at the original size.
(Read more about print sizes >>)
More work for you, but larger
Click this link to a separate dimensioned copy, set to print as a full-size plan.
(Read more about print sizes >>)
If you want to print it in full, you'll need to save it to disk, then open it in a graphics program in order to print it.
Push a pin into the fuselage (D) at the catapult notch position and mark the location of the Jetex mounting clip. Trace the cabin and “G-39-1” number (shown in solid black) on to greaseproof paper, then tape the latter over two layers of black tissue and cut out with a sharp razor blade. Carefully dope the tissue pieces in place and add the, remaining markings (jet intakes, UC doors, etc.) in soft pencil. Go over these lines with a ballpoint pen and put aside until the ink dries, to avoid smudging. Cement piece F to the right side of the fuselage—so that the “clip holes” are covered.

Flying Surfaces

Mark the carving lines on the wing panels (A) with a ball point pen, then carve away the surplus wood (on top only) at the leading and trailing edges, with a razor blade. Finish off to the correct aerofoil section with garnet paper, sanding away the carving lines last of all.

Sand the roots to a slight angle, to allow for the dihedral, then cement the dihedral brace (B) in the slot in one wing panel. When dry, join the other panel to the first. Mark the control surface outlines in soft pencil—on the wings, tailplane (C) and fin (E)—then go over them with a ball-point pen.

Cut out the portion of the fuselage shown in dotted lines and shape the lower edge to conform to the wing aerofoil. Cement the wing in place—checking the alignment in the top and front views—and hold secure with pins, until dry.

Cement the fuselage scrap back in place over the wing and slide the tailplane in the rear slot. Cement a matchstick in the slot in the right wing tip and a paper clip under the same tip to compensate for the offset motor weight. Screw the mounting clip to the left side of the fuselage and cement two 1 in. x 2½ in. pieces of asbestos paper to the fuselage and left wing root, behind the clip.

Now slide the loaded Jetex 50 motor into the clip and check that the model balances level when suspended by a pin pushed into the fuselage top, above the black arrow marked “balance”.

Flying

With the loaded motor in place, face into wind, hold the model at the balance point and launch it firmly ahead on a slightly downward flight path. If the model dives, carefully bend up the trailing edges of the tailplane about ¹/8 in. If it stalls, add a paper clip or other small weight to the nose. The model will most likely have a “natural turn” to the left (due to the offset motor), but more weight on the right wing tip may be added to counteract any violent left turning tendency.

When the glide is correct, light the wick, wait a few seconds and throw upwards at an angle of about 30 degrees. For maximum duration, use a catapult launch, releasing the model right after lighting the wick. The catapult should consist of 10 feet of ¹/8 in. flat rubber tied to a 6 in. dowel “anchor” (or pencil) pushed into the ground. Tie a 20 foot length of thread to the other end of the rubber—and then tie a small curtain ring to the “model end” of ther thead [sic].

  Dean's Midge

Dean's Midge

These views show up the graceful lines of the midget MIDGE. A “droop-dihedral” version was tried, but proved unstable for model use.
- RAF Flying Review, Feb. 1955 (p.37)
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Plan for Midge (A larger copy of the plan is also available to view or download).


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Acknowledgements

 - Article and cleaned-up plan contributed by Gareth Paterson

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