The sky has seen a lot of strange aircraft, and the American designer Charles Zimmerman deserves not the last place on this list. Some names for him are worth something: "flying pancake", "flying skimmer" or even "frying pan that flies."
The inventor began work on this apparatus in 1933. His experiments with a low aspect ratio wing, in theoretical calculations, showed the effectiveness of such a design. It allowed the aircraft to take off almost vertically, hover in the air. And the low drag allowed you to fly faster and use less fuel.
The first device on such a scheme, "Cleon" did not fly - there was a difficulty in synchronizing the rotations of the propellers. But the one-meter model V-162 made a successful flight in the hangar. It was this model that attracted the attention of the military to Zimmermann. Which allowed the inventor to create the same light-engine V-173 aircraft in 1939. It has already been tested "in a serious way", with blowing in a wind tunnel of the test complex in Langley Field (the largest in the world at that time).
The design of the V-173 was a complex wooden frame covered with fabric. There were two engines with a capacity of eighty hp. each, Continental A-80. Five-meter propellers with three blades, special gearboxes, a wingspan of seven meters eleven cm, the length of the apparatus is slightly more than eight meters. The wing area was nearly forty square meters. To lighten the weight, the chassis was not retractable.
Pilot Guyton's tests in November 1942 revealed the difficulty in control, since the load on the rudders was too high: Guyton, with great difficulty and great effort, was able to deploy the "flying skimmer" for landing. But upon landing, the device took only fifteen meters to stop. Gaitogn also noted poor visibility during takeoff.
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For the takeoff run, the V-173 took only 60 m (and if there was a headwind at a speed of 46 km / h, the "pancake" would take off vertically). The maximum speed was two hundred twenty-two km / h, and the flight ceiling was one and a half thousand meters.
A further, military, development of the V-173 was the XF 5U-1, which did not differ from its progenitor structurally, but made of a three-layer material: between the aluminum sheets there was a layer of balsa - light wood. The engines were replaced with the Pratt Whitney R2000-2 (D), a retractable landing gear with hydraulics, a pilot's seat with a catapult and armament: six 12.7 mm machine guns were developed.
The very first "flying slotted" V-173 was donated to the Smithsonian Institution at Silver Hill, Maryland, where it is still under the supervision of Paul E. Garber. In total, this plane made about one hundred and ninety flights. And he frightened by the fact that he was often mistaken for a UFO, giving out sensational news in the newspapers.
