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About the prototype INAV 1A

Soon after a conversation sustained with the General Director of Fligth without Engine, Mister Ernesto V. A. Vignera, in which he showed me his seeing on the future development of the free flight in the Republic, I designed  the INAV 1 for the Argentinean Institute of Free Flight.   
   
From the basis that have been given to me, it would result a training sailing ship that at the same time should be good enough for instruction. To solve this problem in a single glider type I designed the training glider "A"; adding to the same flaps, with what the wing surface increases in 20% and the lift coefficient in 50% , results the version "B" for instruction. This way we obtain the slow flight wanted for the beginner, although the wing loading for a training glider is relatively high.   
Then I tried to satisfy a third desire, this time of the FAVAV, and it was the design of a high performance glider. For this version ("C") I increased the span to 17,2  mts., taking advantage of all the parts of the version "A", including the wing root up to the aileron, resulting this a medium performances high sailing ship. The basic idea around this was the use of the same molds and beds to the maximum , however one will be able to only make the exchange of the wings. The version "D" will follow later with the same dimensions that the "C", adding him a type Fowler flap, to be able to veer more closed, taking this way better advantage of the  intense thermals  of reduced diameter of the continental climate.   
This would allow the clubs to built, with the same kit of construction, the high sailing ship that best adapts to their area. The simplest version , the INAV 1C is fully efficient in flying the weak thermals of great diameter in the oceanic climates. If the clubs have airplanes for towing of great climb speed, an "E" version could be developed for high aerobatics, with aprox. 10 mts. of span, using same fuselage, tail group and wing root.   
   
The economic advantages that brought out the unification of the different types of gliders reside by one part in the series production, and for the other in the simplification of the delivery of spare parts to the clubs. The disadvantage of not to being able to specialize each type of glider to the extreme end of their use, in comparison of the advantages, is thus reduced.   
The instruction of the pilots is also completed with this standard glider, and the students gather the experiences of flying with different gliders with the two - seat (or primary) and in the activity with the different versions, in which the different spans change the moments of inertia and the effectiveness of the commands. This way all the instruction can be carried out with this two - seat and the single - seat model. As in Argentina the flight without engine is subsidized by the State, and few shops for the development of new models of gliders exist, it is relatively easy to standardize the different types, in comparison with the countries of an extensive aeronautical industry, where the competition among the different designers is acting against this aspiration.   
   
Regrettably, due to economic reasons, it has only been possible to build and to test a single prototype of the INAV 1 in the version "A" up to now. The  good results obtained until the moment with this machine give the security that the chosen way is the correct one and that its prosecution will be valuable for the national sailing.  
  
RESULT OF THE FLIGHT TESTS  
  
The prototype of the version "A" has been  tested in April, by Claudio Dori, Head of the Fligth Division of the INAV, giving a very satisfactory result. The effectiveness of the ailerons is exceptionally high, with small forces that increase gradually when increasing the travels. The effectivenesses of the stabilizer and rudder are the normal ones. The spoilers works without vibration and they doesn't produce any movement on the traverse axis in open position. Due to the long travel of dampening of the wheel and the landing skate the irregularities of the ground  are not noticed in take off or landing. The tow hook located in the left side of the fuselage for "center of gravity" tows is also capable for tow by air. In this case one should apply the rudder in the take off and in the tow, and the INAV 1 flies displaced to the right for a span, behind the airplane. The spin entry and recovery characteristics were very good. 
 
 ("Vuelo Silencioso", May of 1954) 

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