Many of the current generation of experienced R/C pilots cut their modeling teeth on COX products in their youth. The COX plastic, ready-to-fly control line airplanes gave thousands of young people their start in model aviation. They were affordable, simple to assemble, easy to start and to fly. Even absolute novices could get them up in the air and usually back down. If the landing was less than successful, a quick dab of glue was all the airplane needed to fly again.

The COX Tailwind Trainer 40 ARF is a purpose-designed, Almost-Ready-to-Fly (ARF), basic trainer that may well introduce the next generation into the world of R/C aviation. Like its control line predecessors, the Tailwind is affordable, easy to assemble and to fly. The label on the box reminds us that COX has a world-renowned reputation for superior engine design and innovative products.

They believe that their new “WINGS” product line will bring high quality ARF models to the hobby market. Their aircraft line will feature laser-cut parts, factory assembled components, fiberglass (not plastic) cowls and wheel pants, US specification hardware etc, and be covered in SIG Aerokote.

The box also states that the Tailwind Trainer 40 ARF was designed as a primary radio control trainer aircraft for the first time pilot. (An ARF is not a product that is ready to fly out of the box. There is some building and assembly still required before you can go flying.)

Because this is an airplane that is purpose-designed to be a primary radio control trainer aircraft for the first time pilot, it is expected to have loads of built in stability and is intended to have you flying on your own as quickly as possible. It also is intended to give you the piloting skills to move on to more aerobatic aircraft.

A standard message to the reader is that a less experienced modeler would be well advised to seek assembly advice. This can be best obtained by joining a Radio Control Flying Club. These clubs are where you will find the more experienced modelers who are most willing to pass on their knowledge and experience.

Although the airplane is intended for use with a 2-cycle motor, it was decided to use an equivalent 4-cycle motor because this was the engine that was available at the time of building. It was also decided to mount the engine sideways to better position the carburetor in relation to the fuel tank and to direct the exhaust gasses away from, and below, the airplane. This makes the model much easier to clean after a flying session.

BOX CONTENTS

Photo 1              Photo 2

The COX Tailwind Trainer 40 comes in a white box with a picture and specifications on the lid. The parts were very well packaged and showed no signs of any shipping damage. The box and the box-lid were used to hold the parts during construction so that none of the parts could become mislaid. A neat building practice is to cut the picture out from the box lid and pin it to your workshop wall for visual reference and inspiration during the construction.

All the major airframe components are pre-assembled. The fuselage comes with the holes for the wing dowels, and the slots for the stabilizer and fin, already pre-cut. However, you have to locate them by feel under the covering. The blind-nuts for the engine mount and the steerable nose landing gear support were already pre-fitted. The engine bay area was already fuel-proofed and ready for the engine mount.

Photo 3

The wings have a black strip underneath on one panel to help in orientation during flight. The Ailerons are not attached and use Mylar hinge material.

Photo 4               Photo 5

The stabilizer is a one-piece item and the elevator will be attached with Mylar hinges. The fin also needs to have the rudder attached with Mylar hinges.

Photo 6

A recommended practice is to open up all of the bags of parts that come in the box. Check that everything is there against the contents listed in the manual. This action serves two very good purposes. First, you find out if anything is missing and second, you familiarize yourself with all of the parts. This will make the building time much shorter and less confusing.

There is a good collection of hardware that comes with the Tailwind 40. The nose-wheel was smaller in diameter than the main wheels. This proved to be necessary to allow the airplane to “sit” level on the runway,

The wing-dowels were approx 3/8” in diameter. This was nice to see because thinner diameter wing dowels tend to bend with strong rubber bands, especially over time. The hardware included a complete set of hinges, control horns, nose gear steering arm, 2-56 pushrod wires, clevises and a spinner.

The large fuel tank would be good for long flight-times. COX had included plenty of fuel tubing to complete the “plumbing” later on in the construction. The six large and very strong rubber bands were included that proved to be up to the task of holding on the wing.

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The main undercarriage was made out of “springy” chrome-plated wire (photo 7). This 5/32” landing gear would handle less than gentle “first landings”. The engine mount (one half shown in photo 8) is not used as the primary support for the nose-wheel leg. The engine mount is designed to accept several different engines. It also permits engine movement fore and aft to aid in the adjusting of the engine weight to achieve the best center of gravity.

The mount was just right when reused to reposition the OS 52 FS engine sideways.  Two of the existing blind nuts positions were used and the other two fitted to two new holes that were drilled in the firewall. The muffler was positioned to direct the exhaust gasses down and away from the fuselage and wing. This made flight operations a very clean exercise.

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The aileron servo tray had been pre-built and shaped underneath to match the dihedral of the wing. This is unusual for an ARF airplane kit and COX is to be commended on this extra quality step. The supplied spinner was not used on the OS 52 FS just to make changing propellers easier during the flight tests. The supplied spinner will work with any 40 or 50-sized glow engine and adds to the airplane’s clean looks. Instead, a Higley aluminum nut was substituted. An 11 x 6 APC proved to be the best propeller for this model and engine combination.

Photo 11

The control horns used three bolts and had a wide base to transfer the working loads of the control surfaces. Horns like these are more often seen in higher priced models.