Cutie Coupe (oz11290)

About this Plan

Cutie Coupe. Rubber competition model.

Quote: "Step into competition or fly for fun with our Cutie. Straight lines and all-balsa surfaces keep it uncomplicated. Cutie Coupe, by Dave Linstrum.

The Coupe d' Hiver (say 'koop dee vair') class is no newcomer on the contest rubber-model scene. The French originated CdH over 25 years ago and it has gained steadily in popularity. It is now flown by so many USA modelers that the AMA has just adopted it as a Provisional AMA Event.

The simple rules restrict only motor weight (10 grams), model weight (70 grams minimum), fuselage cross section (20 cm2, about 3.1 sq in) and type of launch (one point ROG). Scoring is on endurance, with each flight having a max of 120 seconds. These uncomplicated rules (see 1968 AMA Rule Book for detailed rules) and the small field flying made possible by limited motor run are good reasons to try CdH for both AMA and club competition (it is a very popular postal contest event) as well as Sunday sport flying.

There are also good reasons for trying 'Cutie Coupe' as your first CdH, perhaps even as your first advanced rubber model. It is very quick and simple to build, uti-lizing Jedelsky all-balsa flying surface con-struction and a simple box or tube fuselage. You may use a ready-carved Sig folding prop to overcome the biggest problem most beginners have - they can't carve props. The Sig folder is legal in AMA competition and is well worth the price it costs.

Cutie Coupe has been designed with straight outlines for simplicity, but these have been manipulated to give a rakish appearance (stylists might call it the SST look) with more eye appeal than boxy designs. The general configuration and structural techniques have been well proven in many towline gliders built by the author, as well as two previous CdH: 'Spirit' (designed by Jack Daniels of Chicago) and 'Roma.' The latter name I chose because, contrary to historical belief, it was built in a day! You can do the same with Cutie.

Fuselage: I feel that tube fuselages are by far the easiest to build, but many people have mental blocks about them, especially if forms are not available. Use a 1 in diameter dowel or conduit to form the motor tube; a pool cue built up to proper diameter with masking tape rings spaced on 3 in centers makes a fine boom form. Cut a tapered blank of 1/32 'A' grain balsa and soak it in hot water a minute, then wrap on form and bind in place with an Ace elastic bandage. Dry overnight, then glue the seam. By the way, I suggest you build the entire model with an aliphatic resin glue. SigBond and Titebond are both good.

The motor tube is formed in a similar way with balsa; it requires Celastic re-inforcement at both ends, inside or outside, if you like. Cover motor tube with a single piece of silk; this prevents burst motors from splitting it along the grain. Slosh some thin dope inside motor tube to protect balsa against rubber lube. Join boom to motor tube with a 1/32 ring to double boom thickness at this stress point.

Build the pylon with a curved cross sec-tion and a long skirt on the side skin. Sand the complex curve joint between this and the motor tube by wrapping 3/0 sandpaper on the latter and sliding pylon back and forth until it fits. Do not glue pylon in place on either body until balance point of fuselage, with motor, prop, and stab installed, is determined. Then glue pylon on so that CG falls over this point.

The diamond body takes more work but is very sturdy and unique in appearance, yet it is really only a box on edge..."

Cutie Coupe, American Aircraft Modeler, January 1969.

Direct submission to Outerzone.

Supplementary file notes

Article pages, thanks to RFJ.

Corrections?

Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction