SlyCat. Radio control sport plane.
Quote: "If You're Looking For A Small, Lightweight Aerobatic Ship, This One Is A Real Performer On A .25 2-Stroke. SlyCat, by Harry W Gilkes.
Sly cat is one of a series of designs. varying in site from .06 cu in to .60 cu in engine powered airframes; all of which fall under the CAT family banner. While all of these designs bear a family styling theme and have many common features and ideas, they all have their own design parameters and are not just scaled-up or scaled-down versions.
The model featured in this construction article has been designed to be powered by a .20 - .25 2-stroke or a .26 4-stroke engine. For many years I worked as a Styling Feasibility Engineer on the studios of Chrysler UK, Coventry, which included packaging tasks ie obtaining the most space for passengers, luggage, etc in the area left between engine, geartbox, wheels, etc an interesting task but at times a very frustrating occupation. Now, designing R/C aircraft (especially in the smaller sizes) is a somewhat similar parallel, but in this field the task is to get the most compact and lightest structure around a currently available, reasonably priced, receiver and servos. With recent technical advances and price competition, especially relating to mini sized servos and receivers, the design of an acceptable package has become somewhat easier without having to dig deep into the checkbook.
However, in models the size of the Sly cat, I still prefer to use normal size servos for the main pitch and roll surfaces - elevator and ailerons (although a modern mini servo on each wing could be substituted), especially if the aircraft is powered with a more powerful .25, say an O.S. SF type engine whereby the performance and speed could get rather fast and exciting.
Before we get down to the 'cutting and sticking' bit, a few comments on the design features in general:
1. The plans show a normal aileron servo system, and to accommodate this, the servo is sunk low into the wing to provide maximum interior fuselage space, with a plate to provide support for the rx and to prevent the various wiring leads from becoming tangled in the aileron control rods and horns.
(2) The nose length, like all of the other dimensions, was arrived at after much prior experience and calculator bashing - so please don't be tempted to lengthen it to get a monster fuel tank in, you don't need it. The engine bay length is designed to take an O.S. .26 4-stroke. The tank used is a 4 oz type; with a 4-stroke this will run forever. I currently use an O.S. .25 SF (9 x 7 APC), and the times I have run out of fuel are very few and far between. In fact, with this combination, the only time you need anywhere near full power is for vertical figure 8's or big loops, and I mean big loops. Full power for long spells in any other direction means running out of field, sky, space, or eyesight,
(3) This relates to the structure of the fuselage which has laminated sides (no, not the kitchen work top stuff!). This is to help maintain strength around the wing seat/radio compartment, which brings us to the final feature.
(4) The fuselage stowed radio equipment, together with the tank, is all fitted through the top of the fuselage (a common feature on my CAT designs). This is in my opinion far better and easier for installation and servicing.
So. if you have some experience under your belt - both building and flying - you will have no problems either way with the Slycat, as a cooking .20-.25 powered Sunday sports model - or, if you fancy yourself as a hot rod flier, fit an O.S. .25 SF or similar type engine in and go punch holes in the clouds, or knife-edge from horizon to horizon.
Okay. enough sales talk. Lets get to the balsa and plywood butchering.
Construction. Fuselage: As stated, the fuselage is laminated; so start by kitting all the bits and pieces, with the exception of the outer (1/64 in) plywood skins. Start assembly by fitting the inner ply doublers (Aliphatic glue) to the 3/32 balsa assembly by fitting the inner ply doublers (Aliphatic glue) to the 3/32 balsa sides..."
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