finished and test fit to the bottom wing before covering and final assembly.
The tailskid assembly is another distinc- tive feature of the Dorand AR.1. Cut the skid from sheet balsa and the post from 1⁄16-inch diameter reed or rounded balsa. Rounded balsa is used for the bracing struts. Make the small cuff on the tailskid post from paper and paint it silver. The tailskid on my mod- el is hinged to the post with very thin wire and sprung with black elastic thread.
Covering and finish
Like many French WWI aeroplanes, the Dorand’s fabric covering was left in a natur- al varnished finish that took on a distinctive light tan color. The Japanese tissue covering on my Dorand was colored prior to covering using a mix of white, yellow, and brown Pan Pastel chalks. A small amount will suffice. Sprinkle the chalk mix sparingly onto pre- shrunk sheets of white Japanese tissue placed on window glass and gently rub it into the tissue in broad strokes with a fold- ed square of bath tissue. I applied the roundels, numbers and markings to the chalked tissue before covering.
I copied the rudder markings and the wing and fuselage numbers from the plan onto tissue panels sprayed lightly with a white primer. I sprayed the white disk in the wing roundels with primer then applied red tissue rings and blue tissue centers with spray adhesive. The circular white and red fuselage markings are done in the same manner. All that remains now is to cover the fuselage, wings and tail, making sure that the markings are properly positioned on the framework.
Before covering the wings, make a soft wire “U” loop strut attachment fitting for each interplane and cabane strut attach- ment point. Use soft iron wire which can be found in the beading section of most craft stores. A fitting is made by cutting a 5⁄8-inch length of the soft wire and grasping it near the center with the narrow point of your nee- dle nose pliers. Bend the ends of the wire down at a right angle on each side of the pli- ers such that the base of the “U” is about 1⁄16
inch wide. Insert the fitting with the legs straddling the wing rib and passing down through two holes pierced with a pin in the strut attachment point gussets or reinforce- ment disks. Cover the undersurface of the top wing first, then insert each strut attachment fit- ting from the wing top side such that the soft wire legs protrude through the tissue cover- ing on the underside of the wing. Cement the fitting to the wing rib and gussets, then proceed to cover the upper surface of the wing and wing tips. Reverse the sequence on the bottom wing, covering the top side of the wing first then installing the strut fittings from the underside of the wing. During final assembly the strut ends are cemented be- tween the ends of the soft wire fittings. This method of strut attachment is resilient in a crash and provides a convenient rigging point at the end of each strut. Credit for this ingenious attachment method goes to the late Dave Stott, co-founder of the modern Flying Aces Club.
Final assembly
Install the cowl vellum to the front end of the fuselage. Fill the radiator shell wood grain with a sanding sealer, spray it with a light coat of Krylon dull aluminum paint and cement the radiator to the front of the fuselage. Install the instrument panel and cockpit coaming.
Now let’s mount the wings to the fuselage. Despite the unusual bottom wing position, the AR.1 is a relatively easy biplane to set up. Cut out the cabane struts, sand them to a streamline section and paint brown. Glue these to the fuselage sides using a bead of cement along the center of the strut where it meets the fuselage sides. Lay the fuselage on the plan side view to ensure the struts are located accurately as this will establish the proper wing incidence. When the glue is dry, mount the top and bottom wings by inserting the cabane strut ends between the center section strut fit- tings. Use tweezers to gently squeeze the soft wire fittings to the sides of the strut ends and apply a small dab of cement to se-
cure the wire to the strut. Check and adjust the wing alignment as the glue sets. Once the wings are attached to the cabane struts install the interplane struts in their fittings in the same manner as the cabane struts. Insert the landing gear nylon stubs into the mounting gussets on the underside of the bottom wing and cement the assembly in place. Install the tail skid assembly then ce- ment the stabilizer and rudder in place. You have reached the final detailing phase of construction. Carve, paint and install the saxophone exhaust stack then install the bottom wing cabane bracing struts. FAC WWI Mass Launch events require armament to be on the model, so fabricate the observer’s Scarff ring and mount a Lewis Gun. The model must also be fully rigged. I rigged the wings with black monofilament hemming thread, and the tail with heavier 20-pound monofilament fishing line. Install the windshield, observer’s cockpit step, and wing and tail flying surface control horns. I used fine Lycra elastic thread to simulate the control cables.
Flying
Prop and rubber combination is one of the keys to a high performance rubber model. My Dorand AR.1 model flies with a 9.2-inch diameter modified Czech P30 propeller pow- ered by a 26-inch long, 2-loop 1⁄8-inch Tan 2 rubber motor braided to a 23-inch final length. This motor will take around 1800 winder turns and yield a 70+ second motor run.
With a few degrees of down and right thrust and right rudder offset, your Dorand AR.1 model should climb out in a long, grad- ual right spiral, followed by a flat, right-cir- cling glide. In light air, this flight pattern can yield spectacular flights.
My Dorand put up a 9+ minute flight in a slow-moving, mid-morning thermal in the WWI mass launch event at the Geneseo Non-Nats in July, 2011. Happily, the model stayed on the field and I was able to return to the competition. I hope you have as much fun with your Dorand as I have had with mine.
PHOTOS: TOM HALLMAN
WWI Mass Launch action! Flyers (above) line up shoulder to shoulder, last one down wins the sortie. Seven contestants battle it out here. Rejoining the competition after landing on the field following a 9-minute plus flight (at left). Reason for the author, Tom Nallen II, to smile for sure.
FLYING MODELS 29
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