ne of the most important machines the Wright brothers built wasn't an airplane, but a tunnel. Discouraged by the performance of their first two gliders, they suspected that the lift and drag data they had used to design them was incorrect. They resolved to compile their own information, and true to form, designed their own instruments to do it. The 1901 Wright wind tunnel, the lift balance, and the drift (drag) balance were deceptively simple. The tunnel was little more than a pine box; the balances were made from spoke wire and discarded hacksaw blades. But they were ingeniously fashioned and remarkably sensitive. Using these homemade scientific instruments, the Wrights were the first to measure the forces on a wing in fight and use them to determine the design of an airplane.  Their very next aircraft -- the 1902 Wright glider -- was a breakthrough in aeronautical design. It eventually became the granddaddy of every successful airplane built in its wake. If you'd like to read the story of the wind tunnel in its entirety -- how the Wright brothers designed their wind tunnel balances and how they collected their data -- see Lift and Drift.

If you would like to make a replica of the Wright wind tunnel, or if you would just like to study its design to glean a better understanding of the innovative minds of the Wright brothers, we've posted the engineering drawings here. You may download them free with our good wishes. 

However, remember these are copyrighted plans and the copyright holder (us) claims all privileges and protection afforded by law. If you use or distribute these plans, you are bound to these conditions: 

• You may not sell or profit from these plans. 
• You cannot charge copying, handling, postage, or shipping fees. If we can contribute hundreds of hours of research, you can kick in a little paper and postage.
• If you find a mistake on these drawings, you are honor-bound to let us know so we can correct it and make the plans better for those who come after you.
• If you know of or discover better methods or additional suppliers of materials for building this wind tunnel and its balances other than those we describe in the plans or on this web site, you are honor-bound to tell us so we can distribute the information and continue to make this project a better experience, especially for the young people who participate.
• You may make single copies for friends and acquaintances, but you may not publish these plans and offer them to the public in any form, electronic or paper, without written permission of the copyright holder.

There are 9 sheets of drawings, shown in thumbnails below. To save the sheets to your computer, right click on the thumbnail and choose "Save Target As" (in Explorer) or "Save Link As" (in Navigator) from the pop-up menu that appears. Save the JPEG file to a folder on your hard drive. These are big files; some pages are more than 1 meg. So it may take a while to download the entire set, depending on the speed of your modem.

These replicas of the 1901 Wright wind tunnel (top), the lift balance (middle) and the drift balance (bottom) are on display at the United States Air Force Museum

Our replica of the Wright wind tunnel.

Our replica of the lift balance.

Our replica of the drift balance.