Following the IAR-12's failure, the IAR team went back to
the drawing board to see what could be done to boost the plane's performance,
at least on this next version, designated as IAR-13.
For a second time, Elie Carafoli made no significant changes
to the fuselage, but concentrated on the fin and rudder instead. Overall
surface was reduced, and a oval shape was prefered this time in place
of the round one previously used. The wings and the "anti-crash"
pylon were retained as well, whilst the undercarriage ( which consisted
on all of these projects of two main wheels and a tail "skid" ) was slightly reinforced.
The engine chosen this time was a Hispano-Suiza 12Mc, with
12 cylinders placed in a "V", whose output was close to
500 HP at 2200 r.p.m. (rotations per minute). It also offered better
nose contours as well as improved forward view.For the first time,
the propeller mounted was a two-bladed, all-metal Ratier one, instead
of the wooden ones fitted to the previous designs. Armament consisted
of the same pair of sincronized Vickers 7.7 mm machine guns firing
through the propeller arc.
Test flights demostrated that the overall flying and handling
characteristics had significantly improved in comparison with the
IAR-12. Top speed had also been increased to 330 km/h at sea level.
The IAR-13 fighter
In 1933 the aircraft was presented to a ARR comission,with the
hope of obtaining a firm order and throughout the hall year, demostration
flights took place in the presence of most ARR leaders. However, the plane
still failed to impress the senior officials and it did not went into
mass-production. Probably, the idea of a low-wing monoplane fighter was
a bit too revolutionary for these WW1 veterans who had spent their entire
operational career on biplanes.