Knight Twister Imperial (oz11775)


Knight Twister Imperial (oz11775) by Bill Heger 1974 - plan thumbnail

About this Plan

Knight Twister Imperial. Radio control standoff scale model for NSPA Biplane Pattern.

Direct submission to Outerzone.

Plan includes build notes.

Quote: "Construction notes: Soft balsa should be used for all construction except where noted, keep it light-light. When construction changes are made to suit your personal building preferences, leave something out rather than add.

Fuselage: make two sides of sheet balsa with doublers and longerons. Join the two sides on the plan top view with 1/4 in square cross braces to assure correct fuselage alignment. Add the plywood firewall, fuselage top formers and side stringers. Plank the areas shown, using sheet balsa for fuselage side planking and 1/8 x 1/4 in strips for top planking. The removable frontc cowl can be carved from balsa block or molded fiberglass. Arrangements have been made with Hartman Fiberglass RC of Argenta, Il 62501, to produce a fiberglass cowl for this airplane and should be available in time for release of this article.

Wings: the wings are built in one piece, upside down on the plans, with the wing ribs laid on the building surface. This will give a slight amount of dihedral with the taper in the bottom surface of the wing. Make two plywood root rib templates and one plywood tip rib template. Stack enough rib blanks between the two root rib templates to make the straight center section panels. Bolt the stacks together with #4-40 bolts and carve and sand the ribs to shape. Make a stack of rib blanks for each of the four tapered wing panels. Bolt a root rib and a tip rib template to the stacks and carve and sand each of these stacks to shape. Build each wing complete, including the 1-1/4 in balsa trailing edge and sand to finish shape. Cut the ailerons loose in the bottom wing only. Install the aileron horns and re-glue the aileron-center section back onto the wing. The ailerons are hinged and installed after covering. All maple wing mounting blocks and balsa fill-ins should be added to the basic structure before planking.

The fin, rudder, stabilizer and elevators are cut from medium light v' sheet balsa and sanded to shape.

The wings and fuselage are covered before final assembly. The original model is covered with silk and painted with butyrate dope. After covering, apply two coats of clear dope. Install the fin and stabilizer along with the wings and wing mountings. Carefully align all flying surfaces, to 0°-0° incidence making sure all the surfaces are parallel and square with the center line of the model: this operation takes longer on a biplane than other models but it is very important for the proper performance of the model, so take your time and do it right.

Apply three more coats of clear dope, sanding lightly between each coat and wet sand the entire structure after the last coat of dope. Now install the hinges and all control surfaces. Add one final coat of clear dope and two coates of your favorite colors and trim. The entire paint job is rubbed out with auto rubbing compound and waxed.

The engine is side mounted, using a Kraft-Hayes or other suitable radial mount. If the narrow nose version shown in phantom lines on the plans is built, the engine can be mounted upright as shown in the photographs.

The completed model should be carefully checked out for balance, radio operation, control surface neutrals, and direction of travel. Flying weight should work-out to slightly over six pounds. If everything checks out, taxi out and let her go."

Note photos (showing the actual Knight Twister model flown by Bill Heger in 1973) were found online at the AMA site:


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Knight Twister Imperial (oz11775) by Bill Heger 1974 - model pic

  • (oz11775)
    Knight Twister Imperial
    by Bill Heger
    54in span
    Scale IC R/C Biplane Civil
    clean :)
    all formers complete :)
  • Submitted: 28/11/2019
    Filesize: 996KB
    Format: • PDFbitmap
    Credit*: dfritzke
    Downloads: 780

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Knight Twister Imperial (oz11775) by Bill Heger 1974 - pic 003.jpg

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