Plans Service Showcase

1938 aircraft is redesigned for RC

Ben Shereshaw’s Commodore model kit was introduced by the Scientific Model Airplane Company in 1938. Many felt it was the best kit of all of the prolific modeler’s designs, although it was only on the market for a short time.

Bob Oslan’s rendition was structurally redesigned, but built to retain the shape of the original Commodore. He widened the top to accommodate radio equipment and installation, widened the wing center section to fit, and slightly reduced the dihedral. Modified for radio control, it was still under specifications—the original plans called for a 72-inch wingspan, but the actual layout measured 71 inches.

An Enya .29 weighing 4¼ pounds was used for power and proved to be good for Texaco competition. “The power/economy combination is more than ample to get well into thermal territory, and the Commodore’s glide is excellent—it milks life with the best,” Bob noted. “If sport flying is your thing, the ship is strong enough for aerobatics, and it performs them well.”

Bob stressed that the Commodore’s build was not for beginners; however, a moderately experienced builder would have no difficulty.

The fuselage build began with the crutch, and would quickly take shape. There were ¼-inch square pieces that formed the top of the cabin. After all of the stringers were in place, the landing gear assembly was installed, and the ⅛-inch sheet fuel tank platform was added. The engine cowl was made by tack-gluing the cowl block to the firewall then shaping it to flow smoothly with the fuselage. The shaped block was then hollowed to approximately ¼-inch thickness.

The vertical and horizontal stabilizers were straightforward and did not need much explanation in Bob’s article. He also noted that the wing construction was simple and designed to facilitate easy and accurate assembly of the three sections.

The choice of covering was left to the builder’s discretion, but the Commodore was designed to be able to sustain flight loads if it was covered in plastic film. Bob recommended the silk-and-dope method for maximum strength, but to use a plasticizer in the dope or non-tautening dope if this method was chosen.

The prototype of the Commodore took off on its maiden flight at approximately half throttle and maintained a steady climb. The touchy rudder was easily corrected by moving the pushrod in on the servo arm. Stall recovery was good because of the clean lines.

“If you flare out for a landing three feet too high, the bottom doesn’t drop out—she just keeps right on flying,” Bob stated. “Of course, if you’re really determined, you can smash up anything. But the Commodore will tolerate a whole bunch of mistakes before you get into too much trouble.”

He noted that he wouldn’t be surprised if the Commodore became a builder’s favorite airplane.

The Commodore was featured in the February 1981 issue of Model Aviation as AMA Plans Service number 325 and is available for $24, plus shipping and handling. AMA members can access the MA Digital Library on the magazine’s website to read more about this airplane and its construction. See page 145 or go to www.modelaircraft.org/plans.aspx to order.