Captive Column . Com

arrow1.gif (893 bytes) Time Line - 1970: Aircraft Float Prototype...

This Aircraft Float prototype was built to prove the concept of using Captive Columns for aircraft applications. This prototype was a good example of how easily the Captive Column can be made into an aerodynamic shape. The properties of clean lines and light weight make the Captive Column an ideal method of aircraft construction. Even though the Captive Column can be made to take the final shape of an application, it is not necessary to do so. The Captive Column can also be used as a component in construction.

This particular structure was tested at San Jose State University in 1970. While the Captive Column has been evaluated at universities and proven to work as claimed, it is still not being taught in engineering classes. As far as we know, engineering students are not even exposed to the concept. As a result, universities across the United States have been churning out engineers with incomplete training for over 32 years.

The following photos and text describe this prototype:

Only 45 pounds This Captive Column Aircraft Float prototype weighed only 45 pounds and was easily held aloft by one person. Elimination of bulkheads permitted clean lines with a smooth, fastener free surface. (15k)
Test Fixture A test fixture, made of 2 x 6 Douglas Fir boards, attached to a fitting built into the structure. Similar fittings would attach the float to an aircraft undercarriage. (18k)
Getting Tested A load was applied to the center of the Captive Column test fixture. At 3,500 pounds, the fiberglass core element began to buckle, but did not break. An air bag under the float simulated water. This test was done at San Jose State University. (23k)


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Copyright 1998-2004 by Lawrence R. Bosch.