This hovercraft is an old non-Didik design. It was constructed using a 110HP McCollough 2 cycle engine and a 4 blade aluminum propeller. The body is made out of shaped Styrofoam covered with fiberglass. The entire craft weighs approximately 300 lbs and is capable of flying over objects up to 8" high. The top speed at on solid flat ground is about 25 miles per hour. The speed on water is only 15 mile per hour. The lower speed is a result of wave action and water resistance and displacement. The top speed on ice exceeds 45 mile per hour. This non Didik hovercraft is shown since it is interesting how the designers approached the problem of weight reduction and at the same time, providing high strength. One problem with such styrofoam designs is that styrofoam is destroyed if it comes in contact with gasoline and so it must be completely shielded, such as with fiberglass. Some people have used water soluble white or wood glue as a coating over the styrofoam. Fiberglass over the styrofoam creates a very strong body, though creating a mirror finish on the fiberglass can be difficult. If you use auto repair body filler to smooth out the fiberglass, the weight of the body increases. Further, body filler is not as strong as the fiberglass and, in the case of a hovercraft, it can come lose from the vibrations. On the other hand, you can sand the fiberglass, but in order to do this, again you must have a thicker fiberglass shell, which also dramatically increases the weight. Nevertheless, this technique is a way to create interesting shapes quickly and relatively cheaply.   Frank Didik built a one person inflatable hovercraft, using a low HP leaf blower as the air supply. The unit was approximately 8 feet in diameter and had a 6" skirt around the perimeter. Steering was accomplished by leaning towards the direction that you wanted to go. This simple unit was able to fold into a small suitcase and was capable of lifting a 185 lb person, however the low energy output of the engine did not provide adequate power to propel the person at more than a walking pace.   Starting in the late 1940's, some people have built small hovercrafts using a basic 3.5 to 5 HP grass cutter engine and a 18 to 25" propeller facing down. These units are very noisy and tend to vibrate very badly, but they do work. As with the Frank Didik designed inflatable hovercraft mentioned above, these units are steered by leaning towards the desired direction of travel. You can probably find information on these units on other internet sites or perhaps find plans to build them behind many science and hobbyist magazines. Bookmark this site (in your favorites section) by pressing CTRL D key now.