24k T-47-4 from Russian Power Site
, traced down to
New interceptor (based on T-3 family) with improved
radar and armament was flight-tested in first half of 1958 - even before the
program was officially approved. Two T-3 prototypes (assembled at
Novosibirsk factory No153) were fitted with with new 'blown' cylindrical nose section and used for preliminary
airdynamic studies under designations
PT-8-4 and PT-7.
PT-7 (under new designation T-47-3) eventually became the first aircraft of new
generation, when the PT-8-4 (later designated T-47-2) was lost in September
1958 accident. The first
prototype (T-47-1) was transferred to LII (September
1958) for powerplant evaluation and did not participate in flight tests.
Official flight of new interceptor with new radar housing, engine and underwing hardpoints took place on October 25, 1998.
In April 1959 T-47-3 was joined by another prototype T-47-4 and in June - T-47-5. In period between November 12, 1959 and
April 7, 1960 'compressed' program of K-8M (with heat-seeking heat) evaluation
was carried out. At the end of this trials two more prototypes (T-47-7 and T-47-8) were ready and trials of a radar-guided
K-8M took place. T-47-6 did not participate in the program - it was delegated
for K-9 missile, intended for new T-37
Redesigned nose, large underwing missiles demanded to install more powerful engine and to provide more room for fuel.
Modifications (extra tanks in wing roots and after-wing fuselage section, AL-7F-2
engine) were implemented on T-47-8. On April 1960, all T-47 were upgraded to this standard.
During those trials about 250 flights were performed.
Second stage of trials (475 flights, April 26, 1960 to June 8, 1961) was dedicated mostly to armament (radar, missiles)
evaluation under conditions of real intercept (targets). In November 1960, even before official end of trials, the State
Acceptance Commetee recomended series production of the aircraft.
In July 1961 T-47-8 was presented to public during Tushino Airshow.
Governmental Order to start series production was issued in November 1961, in February 1962
it was officially accepted for service under designation Su-11-8M
40k T-47-5 with K-8M
Russian Power Site
, traced down to