Hot Canary (oz6985)


Hot Canary - plan thumbnail image

About this Plan

Hot Canary. Radio control biplane pylon racer.

Quote: "A pair of unique and well-designed racers for Formula I and Formula II/FAI NMPRA racing. These are just as competitive as the usual planes. Hot Canary, by Bob Seigelkoff.

THE HOT CANARY is a really different airplane. A biplane racer is unusual enough, but designer-builder and flier Bill Warwick wanted to see the pylons as he banked into the turns so he put the upper wing behind the pilot!

After seeing the Hot Canary at the 1970 Reno races, we felt the urge to build a miniature pylon racing version. The design fits both the FAI International racing rules and the AMA Formula II event. Total surface area is 705 sq in (698 required for FAI). It is an excellent flyer, but control surface movements must be minimized. An eighth of an inch up and down on both the elevators and ailerons should be more than sufficient for trial flights. Movements can then be adjusted after trimming and altitude adjusting flights.

The bane of any fast pylon racer is that too much elevator will induce a snap roll, and at racing altitudes this is an immediate disaster – a characteristic of any model turning pylons at over 100 mph. Consider the wing loading of a five-lb plane at six or eight g's with 600 sq in wing area. That's asking the wings to support a 40-lb weight (or 154 oz/sq ft wing loading)! Flying on the safe side of the elevator travel is essential.

It's hard to believe, but the first prototype, with a plain wood finish, had its wings an inch and a half farther aft than shown on the plans. What a goofball-looking thing that was, but it flew, and fast. In several match races against a competitive Formula I Ballerina, the Hot Canary held its own.

Because of too much elevator travel, the first prototype ended in a snap roll at about a ten-ft altitude in the No.2 pylon turn. The second prototype, with its wings moved forward, appears far less sensitive in this respect, but it is still important to keep all control throws down. Do not fly with a CG aft of that shown on the plans.

Construction. Building the Hot Canary poses no problem. The fuselage is a square box with no 'fancies.' Begin with the fuselage side assemblies, adding the ply doubler to the balsa sides with contact cement. Then add the 1/4 sq longerons and 1/8 x 1/4 uprights with Titebond, making right- and left-hand panels. Lightly score the ply doublers at the bend points (shown in the plan view) and, with a straightedge over the scored line, gently crack the side assemblies so that a sharp bend point results.

Begin fuselage assembly by gluing the sides to the intermediate cabin area bulkheads. Add several temporary diagonal braces top and bottom to keep things square, then add the firewall, top and bottom sheeting, landing gear mount, etc. The 1/8 wing doublers should have the wing hold-down block cutouts cut right through, serving as doublers for the anchor blocks..."

Hi Steve - Here is Bob Seigelkof's Hot Canary from American Aircraft Modeler magazine issue 08-71. The model was featured on the cover as shown.

Direct submission to Outerzone.

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