Intended as the series version of the IS-1 polymorphic
single-seat fighter, the IS-2 embodied some aerodynamic
refinement, but, flown early in 1941, did not incorporate
the results of the flight testing of its predecessor.
The principal changes introduced by the IS-2
were replacement of the M-63 engine by a similarly-rated,
but smaller-diameter, Tumansky M-88 14-
cylinder radial; replacement of two of the four 7.62mm
guns by 12.7mm weapons and re-design of the tail surfaces,
including introduction of a cantilever tailplane.
Realisation that the variable-geometry arrangement
would be difficult to maintain under wartime conditions
and the fact that battle damage to the actuating
mechanism would inevitably prove disastrous, coupled
with the comparatively low level speed performance
attainable, led to the discontinuation of development of
the Istrebitel' Skladnoi upon the commencement of the
German assault on the Soviet Union. A more advanced
model, the IS-4, was abandoned without flight testing.
|A three-view drawing (1650 x 1123)|
| Wingspan||8.60 m||28 ft 3 in|
| Length||7.10 m||23 ft 4 in|
| Max. speed||507 km/h||315 mph|
|Mike West, 12.02.2012|
I find the NS series delightful, but when you see just how little extra lift is generated by the biplane configuration, you wonder why he bothered. Fundamentally, the biplane configuration provides much more structural benefit than lift, so it's no surprise that the NS series was a dead end.
Do you have any comments about this aircraft ?