HANGAR 9: Extra 330S

Giant-scale aerobatic fun!

The Extra 330S is Hangar 9's newest plane in the 33% category. Designed by veteran Tournament of Champions pilot Mike McConville, it incorporates design features and enhancements that have been gleaned from his many years in competition. The Extra 330S will satisfy the needs of serious competitors, but it is also an excellent, stable-flying aircraft. It can be fine-tuned to perform precision aerobatics and tweaked to fly wild, 3D-style aerobatics as well.

WHAT'S IN THE BOX?

The Hangar 9 Extra 330S arrives in two boxes. The larger box contains the balsa-and-ply fuselage, built-up balsa rudder, fiberglass painted cowl and wheel pants, canopy, wing tube, aluminum landing gear, decal set and a 48-page manual. The second box contains the right and left wing panels with ailerons; these parts are individually wrapped for protection. The left and right stabilizers with the elevators are also wrapped and taped down for protection during shipping. You'll need to provide an engine, radio gear, your favorite hardware and, of course, a really cool pilot figure. Hangar 9 offers a complete, 1/3-scale hardware package (sold separately for $149.95) that's made especially for the Extra 330S.

CONSTRUCTION

As with nearly all almost-ready-to-fly (ARF) planes, I began my construction by removing the wrinkles in the covering. The Hangar 9 UltraCote did not require much shrinking, but because this is such a large airplane, you should allow yourself enough time to work over all the surfaces with a covering iron. I also gathered up all the hardware necessary for completing the plane. At the time I was building this plane, Hangar 9's 1/3-scale hardware package wasn't yet available, so I used high-quality Du-Bro products, all of which fit perfectly.

WING CONSTRUCTION

The manual begins with instructions for assembling the wings. You only have to hinge the ailerons and install the servos. Because this is a big plane, it requires two servos for each aileron. I selected the JR DS 8411 digital servo for all of the control surfaces because of its quick response and powerful torque. I also used a JR MatchBox on each of the ailerons, the elevator and the rudder to make it easier to synchronize the servos for each surface. Each servo required a servo extension that I attached firmly with shrink tubing; this will prevent anything from coming loose inside the wing. After I had screwed the servos in tightly, I used the methods outlined in the instructions to attach the control horns to the ailerons. Du-Bro's heavy-duty control horns were great for this application; they make solid, reliable connections.

Detailed instructions explain how to install and hinge the ailerons; the same method is used for the elevators and rudder. The control surfaces are drilled out for Robart hinge points. I like to use Vaseline on the knuckles of the Robart hinges to prevent epoxy from seeping in during assembly. I also roughen up the hinge points with 100-grit sandpaper. It is important that the hinge pivot pins be parallel and flush with the aileron's leading edge. Install the hinge points in the ailerons first, and allow them to dry. After the epoxy has fully cured, I work each hinge point back and forth until the hinge can move throughout its full travel without resistance. Attach the ailerons to the wings using this same method. Press the ailerons onto the wing so that there is a 1/64-inch gap between the aileron and wing's hinge line. After the epoxy has cured, deflect the surface fully until there is full travel with little or no resistance.

The large hinge gaps on the control surfaces of the Extra 330S need to be sealed to prevent any flutter. Hangar 9 suggests that you use a strip of 3-inch-wide clear UltraCote that has been folded in half and ironed onto both sides of the hinge line (wing and aileron). This method is easy and works quite well. Sealing the aileron, elevator and rudder hinge lines is extremely important. If you fail to do this, the resulting surface flutter may very well cause a crash.

I centered the servos by connecting them to the receiver and turning on the transmitter. I then hooked up the aileron control rods to the control horns and servo arms, The wings were now finished and could be set aside; I attached them later when I was ready to adjust all the control surfaces.

RUDDER AND ELEVATOR

Install the rudder and elevator servos in the rear of the fuselage. Each of these servos also requires a servo extension and is held together with heat-shrink tubing. There is a servo for the elevator on each side and two servos (one on each side) for the large rudder. Install these control surfaces using the same method (Robart hinges and UltraCote for the hinge gap) as was used for the ailerons. After you've hinged the stabilizer and elevator, attach them using two stabilizer tubes. Insert two metal tubes through the aft end of the fuselage (just below the rudder fin), and then slide the stabilizers onto these tubes and secure them with 4-40 bolts screwed into each tube. This method of attachment allows easy stabilizer removal when you transport the plane to and from the field.