|About the prototype INAV
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
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
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