Piper Arrow 2

Model Airplane News, Apr 2004 by Onorato, Jim

AVIOMODELLI

Sport-scale sedan of the skies

The Piper Arrow 2 is one of the most rugged, reliable and attractive full-scale trainers in the air today. It offers the perfect combination of quality and features to make it suitable for training, business, commercial and private use. Its superior quality and reliability have made it a staple craft in Piper's fleet for 30 years. Popular worldwide with flight instructors, the Arrow is also an aircraft that flight school graduates often purchase for themselves. Since I am neither a flight school graduate nor wealthy enough to afford the full-size version, I was happy to try Aviomodelli's kit of this classic six-seater.

THE KIT

Though advertised as a 50-percent ARF, Aviomodelli's Piper Arrow 2 kit does require a fair amount of work. The Arrow is actually a balsa and ply kit with vinyl- (or resin-) covered, foam-core wings and tail feathers. The kit includes balsa and laser-cut ply parts for the fuselage, balsa stripwood, vinyl-covered foam wing panels and tail feathers, a fuel tank, a motor mount, a spinner, wheels, vacuum-formed windows and windshield, decals, plans and a very complete hardware package. There are also a number of ABS parts, including the cowl, wingtips, stab tips, rudder fairing, servo boxes, instrument panel, antenna, taillight and seats. Instructions are provided in several languages right on the plan and include a complete list of every part identified by number, name, material, size (in millimeters) and quantity. Although the plan is not full-size, it does show every part by its identification number; I found this very helpful. In addition, the parts are numbered consecutively in the order in which they are used-also very helpful.

CONSTRUCTION

The first thing I did before starting construction was identify and number all the laser-cut parts while they were still in the plywood sheets. I also numbered all the other wooden parts, including the stripwood.

* Fuselage. I started construction with the fuselage, which is the part of the Arrow that requires the most effort. It is basically a plywood frame with the nose section, the cabin and the upper surface planked with balsa stripwood. All of the plywood parts are laser-cut and interlock to fit perfectly. This made it rather easy to keep things in proper alignment. Very small nails are provided to attach the plywood parts, but I chose not to use them, as I was afraid they would split the plywood. I used 5-minute epoxy on the plywood parts and aliphatic glue, which is easy to sand, for the planking. A large hatch on the bottom of the fuselage provides access to the radio equipment, which, when installed, is completely hidden under the seats.

* Tail feathers. The tail feathers came next. Since these are vinyl-covered foamcores, all that was required here was to separate the elevator and rudder from the stab and fin and to apply balsa to the exposed leading and trailing edges and thin plywood to the ends. The ABS stab tips were attached with medium CA. I inserted the wing tube into the fuselage to make sure that the stab was aligned properly, then I glued the stab and fin to the fuselage with 30-minute cpoxy. I didn't hinge the rudder and elevator until after the plane had been covered.

* Wings. The Arrow uses plug-in wing panels, and I completed those next. I numbered the flaps and ailerons before I cut them from the wing panels so they wouldn't get mixed up. Then, I covered all the exposed edges with balsa and plywood as I had done with the tail feathers. Pinned hinges are used for the ailerons, but the flaps use torque rods that are connected to a servo in the fuselage. These were not attached until after the plane had been covered. Two ABS servo boxes provided for the aileron servos were cemented into the cutouts in the wing panels, and the servos were attached to the box covers. I thought this was a very clever way of installing servos in a foamcore wing. The wing stiffeners, into which the metal wing tube fits, were made by laminating five laser-cut plywood parts and then gluing them into the wing with 30-minute epoxy. The stiffeners also hold the main landing gear that I attached after the plane had been covered. I attached the ABS wingtips with medium CA and epoxied the root ribs and the anti-rotation pins to the root ends of the wing panels. Once the wings have been slid onto the metal wing tube, they are held in place by two spring retainers attached to hook eyes in the wing. These were screwed into dowels that were then epoxied into the root ends of the wing panels. The final step was adding the tapered sections to the leading edges of the panels.

* Details. Next, I painted the inside of the cabin with flat-black acrylic paint and glued in the vacuum-formed windows from the inside. The ABS seats come in three sections. I painted the seats tan and the floor black and then installed the seats in the fuselage. This was a little tricky because the seats fit very snugly, and the only access is through the bottom hatch. I didn't install a pilot figure but made the windshield removable in case I decided to add one later.