Popular Woodworking 2003-06 № 134, страница 70

ABOUT THE 1903 FLYER, THE FIRST TRUE AIRPLANE

After a failed attempt on Dec. 14,1903, by Wilbur, the Wrights flew the world's first powered airplane at Kitty Hawk on Dec. 17,1903. Beginning at 10:35 a.m., Orville flew it about 120 feet (in about 12 seconds), Wilbur, about 175 feet; Orville, about 200 feet, and, about noon,Wilbur flew it 852 feet in 59 seconds.

This biplane had 40.3-foot span; 0.83-foot anhedral; 6.5-foot chord; 6.2-foot separation; 510 square-foot area; 1/20 camber; 48 square-foot double horizontal front rudder; 21 square-foot twin movable vertical rear rudders; 21.1-foot overall length; and weighed 605 pounds.The right wing was 4" longer than the left to compensate for the extra weight of engine.

This was the only aircraft the Wrights tried to preserve. Damaged by wind after the fourth flight, they returned it to Dayton; Orville sent it to the Science Museum in London in 1928; since 1949 the Smithsonian has displayed it as the world's first piloted powered airplane.

Products Laboratory, you'll find that ash and spruce are among the strongest woods in all three of these categories.

Aircraft Design

The strength of the wood in the 1902 Wright Glider does not completely explain its remarkable durability, however. The other half of the story has to do with the design of the aircraft.

When Will and Orv set out to build this airplane, they knew they were going to crash it. They were teaching themselves to fly. Their previous gliders, built and tested in 1900 and 1901, had shown them that piloting required great skill. And because these previous gliders hadn't flown all that well, the brothers hadn't yet acquired that skill. So Will and Orv built an airplane that would protect them in the event of a crash and was relatively easy to repair when damaged.

A biplane structure offered the necessary strength and resilience. Two wings, one above the other, were trussed like a bridge. Although the individual wings were lightly built, when the structure was braced with wires under tension, it became incredibly

strong. When the structure slammed into the ground, the force of the impact was quickly distributed throughout the frame via the bracing wires. Instead of the wooden parts at the point of contact taking the blow, the force was divided up so each part absorbed some of the impact. As a result, the glider was able to withstand crashes that would have

destroyed other structures. And because the biplane formed a cage around the pilot; he, too, was protected from harm.

Some damage was inevitable, however. To make the glider easy to repair, Will and Orv decided to lash the parts together rather than fasten them with hardware. If a part was broken, all they had to do was cut the lashes, slip out the old part, then lash a replacement in its place. If a major part such as a spar broke, it could be quickly splinted and wrapped with lashing cord. In some cases, the repaired part actually became stronger than it had been before it was damaged.

Lashing may seem a strange assembly method to those of us who prefer to fly on aircraft that are held together by something stronger, but it was a logical choice for the Wright brothers. In their day, every kid learned marlin-ship (knot tying) as soon as they could tie their shoelaces. Today, the only vestige of this ancient skill is the knot-tying section of

the "Boy Scout Handbook." But in Will and Orv's day, it was essential. In the days before adhesive tapes, lashing was the best way to make quick, strong, temporary joints. The wax-covered linen cord that Will and Orv used to lash their airplane together was the Victorian equivalent of duct tape.

Just how well this system worked for the Wright brothers was made apparent to all of us when Maj. Dawn Dunlop, an F-15 Eagle-driver and test pilot for the U.S. Air Force, became the first pilot to complete an inside loop in a Wright glider. Floating in for a landing, Dunlop lost forward speed and began to slide backwards in the air. A gust of wind caught the underside of the wings and rolled the glider onto its tail, its back and then its nose. It rolled right-side up again before the launchers could catch it.

I came running up and found Dunlop unhurt, protected as she was by the biplane cage and the soft sand. The aircraft was less

Lt. Cmdr. "Santa" Ohman (USN) brings the 1902 Glider in for a smooth landing.Ohman is a Navy test pilot whose day job involves landing F-18 Hornets on the USS Kitty Hawk.

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Popular Woodworking June 2003