Airmark Cassutt. Quarter scale radio control model racer for .60 engines.
Quote: "Go quarter-scale with NR Blackwell's racer for .60 motors - just 45in span!
In 1954 Captain Tom Cassutt designed the Cassutt Special, a single-seat racing aircraft. Following the success of the prototype many were constructed by home builders in the US. In 1969 Airmark Ltd started to produce the Airmark Cassutt in the UK. Two derivatives were produced, the IIM and IIIM, the main differences being in the width of the fuselage and of the thickness of the wing.
Both types were powered by 85-90 hp engines, normally of the Rolls Royce Continental variety which gave a top speed of around 200mph. The fuselage, fin, rudder, tailplane and elevators were constructed of welded steel tube, the wings had built up ribs and laminated spruce main spar. The cowl is from fibreglass and metal and the whole unit was reputedly stressed to + or - 12 G.
Building your Cassutt. Nothing too complicated here, but I would expect anybody building this model to be reasonably experienced at building from plans as it is not really suitable for a second or third model. Cut out all parts and make a kit. Laminate sides and doublers and add top 1/4 in sq balsa. Attach 12 and F4 and undercarriage plate. When dry add the 1/2 x 1/2 in hard balsa servo tray mount. Next add formers F5-8 and 5/16 x 1/4 in fin post. Now add fin core (note offset) and 1/4in sq balsa spine and 1/4 in sq spruce keel. Next epoxy in F1 and D fillets. While that has been going on it will have been no hardship to build two wing panels.
When the fuselage is dry check the wing panels against the fuselage. If all is OK put the panels back on the building board and sheet the top and bottom with 1/64 ply (if you have used foam wing panels they should be fitted with spars as per the built up wing with 2-7/8 in of the spars protruding from the inboard end of each panel and 1/16 balsa tip ribs on the outboard end).
Next add the 1/2 in sheet wing tips noting that they stop 50mm short of the false TE. Back to the fin. Add two pieces of 1/4sq x 1/4in long spruce to the rear of F8, then add the 1/4 x 1/8 top and diagonal rod to the fin and finally attach FR3. Now we return to the wings. Put the aileron torque rods into the false TE and epoxy the wings into the cutouts in the fuselage making sure everything is aligned correctly. When dry, sheet in the top of the rear fuselage and the areas just to the rear of the cockpit..."
Cassutt, RCM&E, January 1991.
Direct submission to Outerzone.
Article pages, thanks to RFJ.
Did we get something wrong with this plan? That happens sometimes. Help us make a correction
* Credit field
The Credit field in the Outerzone database is designed to recognise and credit the hard work done in scanning and digitally cleaning these vintage and old timer model aircraft plans to get them into a usable format. Currently, it is also used to credit people simply for uploading the plan to a forum on the internet. Which is not quite the same thing. This will change soon. Probably.
This model plan (like all plans on Outerzone) is supposedly scaled correctly and supposedly will print out nicely at the right size. But that doesn't always happen. If you are about to start building a model plane using this free plan, you are strongly advised to check the scaling very, very carefully before cutting any balsa wood.
© Outerzone, 2011-2018.
All content is free to download for personal use.
For non-personal use and/or publication: plans, photos, excerpts, links etc may be used, provided that full and clear credit is given to Outerzone with appropriate and specific direction to the original content i.e. a direct hyperlink back to the Outerzone source page.
Unauthorized use and/or duplication of this material without express and written permission from this site's owner is strictly prohibited. If we discover that content is being stolen, we will consider filing a formal DMCA notice.