The depression of the early 30's forced him out of general aviation so he designed kites that he had his mother make for him. Together they would make large kites which they could put advertising messages on for different events. In the late 30's Jalbert joined the United States Rubber Company in Naugatuk, Connecticut in order to fabricate barrage balloons (blimps). His past experience of using balloon and kites for advertising, and his knowledge of various types of rigging, were a great asset to him in his new line of work.
While at United States Rubber, Jalbert learned how to fabricate static air inflated balloon fins and rig belly bands along the outer skin on large barrage balloons so that they would maintain a stiff internal pressure. At that time, Jalbert did not realize that 25 years later, the experience gained on the static air inflated fin and the distribution of pressure on balloons by belly bands, would be the basis of a new aerial device. As a result of this combined knowledge that Jalbert had gained, came an invention which has become known to the world as the Jalbert Parafoil.
From the late 30's to the 50's, Jalbert's activities were entirely spent on the research of kites and kite-balloons, with some dabbling in the parachute field. In 1952, Jalbert developed the first basically different type of parachute, since Lenoardo Da Vinci's first concept from the 1400's. It had an incredible difference from the conventional round chute, as compared to the standard accepted chute of that time which only had one center of effort. Jalbert came up with the Multi-Celled Parachute which multiplied the center-of-efforts and increased the drag coefficient by as much as 20 percent.
Since sky diving was being introduced at this time, Jalbert became very interested in the problems of this field. With the help of qualified jumpers, Jalbert made many types of parachutes trying to find a canopy configurations that, thru control lines, would produce directional control and a glide ratio of 3 to 1. After about five years of time and the expenditure of a great deal of money, on all types of modified canopies to produce glide, Jalbert decided on another approach.
One day when Jalbert was flying back from Patrick Air Base, he looked out at the wings in which he was traveling on and thought to himself. To really travel from one place to another and achieve a 3 to 1 glide ratio, you need to have a wing. Birds do not have cups like conventional or multi-celled canopy-type parachutes and neither do airplanes. They have wings!!! Then why not make a wing from fabric? Upon landing at the Boca Raton base, Jalbert opened the gas tank cap on the wing and took a yardstick and measured the depth. Then he proceeded to the drawing board back at his laboratory.
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