Flying model airplane resources
 
 

 
 
(R/C Makeover... pg2)

Airframe Modifications

The fuselage didn’t need any major changes to handle the extra weight of the R/C gear, but I did use gussets liberally throughout the structure. You can see from the photos how they’re placed around the areas supporting the wing, radio gear, and landing gear. Another fuse modification was the engine mount, which is simply a 1/16” sheet floor glued between the first two formers, with a hard balsa motor stick glued to it. Thrust angles were built into the motor stick before attachment (see motor mount details below).
 
  SPECIFICATIONS


Kit - Jimmie Allen MC – BA Parasol, from Easy Built Models.

Motor - GWS LPS-B2C-C (11.81 grams) http://www.aeromicro.com/

Prop - GWS 2-Blade 7.0" x 6.0" Slow Flyer Propeller)

Receiver - MPI MX6800 PICO

Speed Control - Pixie-7p (Programmed for 6 volt cutoff)

Servos – (2 ) GWS Pico BB

Battery Pack - - 2 * 230 mah Lithium Polymer cells in series http://www.smallrc.com/

Flying Weight - 102 grams (3.6 oz)

Wing Loading - Approximately 4.9 oz per square foot

Only one modification was made to the wing: a short 1/16” sq. spar added to the upper center section to strengthen it. This also serves to take stress from the rubber band hold-downs off of the tissue covering. I elected not to add any washout to the wing.

The tailpieces each have an extra 3/32” square spar to accommodate hinges, and some 3/32” balsa in the areas where control horns attach. Hinges are the “sewn” type, made with cotton thread. The horizontal stabilizer differs from the original design in that it’s built as one piece and slotted through the fuselage, rather than attached to the fuselage sides as two halves. Left and right elevators are connected with a short piece of ‘U’ shaped music wire to clear the rudder.

In the pursuit of lightness I left some of the scale-ish details off the model, including landing gear fairings, wheel pants, and pilot’s headrest. The plastic wheels in the kit were replaced with lighter ones that I made from foam and balsa. I used 1/32” music wire for the landing gear, and shaped it so that it extends up into the fuse more than shown on the plan. The entire model was covered with tissue and given three light coats of clear Krylon fixative. Afterwards, the fuselage was sprayed with a coat of dark blue acrylic enamel.