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Info Eduard - December 2011
HISTORY
eduard
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Info Eduard - December 2011
MiG-21BIS á la Eduard
Photo at the top: MiG-21BIS-D, Croatia Air Force,
2009 (photo: Ondrej Maliniak)
Martin Král
One of the kits that we are releasing this
month is of the MiG-21BIS. Given that this
specic variant is shrouded in some confusion
with respect to development and its intended
role, it is prudent to say a few words on the
theme.
Towards the end of the sixties, the MiG
design bureau embarked on a modication
program of the design that subsequently was
given the designation MiG-21BIS. It was an
extension of the MiG-21SM, and as opposed
to all previous members of the family, was op-
timized for air to air combat in tight maneuve-
ring ghts at low to medium altitudes.
The specications issued would require the
MiG-21BIS to undergo several structural
changes that would separate it from its pre-
decessors, the MiG-21SM and SMT. First and
foremost, the uprated R-25-300 engine was
installed, that could develop 9720kg of thrust.
This was the nal, and one could say ultimate,
development of the R-11 that powered the
rst and second generation MiG-21s. Thanks
to the more powerful engine, the climb rate
rose to 225m/s as opposed to 120 to 130m/s
in the SM powered by the R-13-300 and
140-150m/s with the F-13 powered by the
R-11. Lower fuel consumption and additional
fuel housed in the spine at least partially alle-
viated the greatest shortcoming of the type
- inadequate range.
Poor experience with the MiG-21SMT, that
housed additional fuel tanks in a greatly en-
larged spine that carried with it drastic per-
formance penalties, was used in the redesign
of the spine on the MiG-21BIS. The spine was
smaller, and in terms of dimensions and shape,
was a compromise between the same feature
in the SM and SMT. The fact that this appro-
ach was successful is illustrated by its retrot
to earlier SMT airframes.
One of the nal modications was the sub-
stitution of titanium for formerly steel com-
ponents. This was expected to lighten the
aircraft and increase allowable limits which
were increased from +7g to +8.5g. The ra-
dar was improved to RP-22M Sar (‘Jay Bird’)
standard with a scan range of 30km and an
attack range of 15km with partial capability
of identifying targets against ground clutter.
The radar was installed in the intake shock
cone. The armament consisted of UB-32A
rocket pods and air-to-air R-13M and R-60
missiles.
Ofcial integration of the type into the So-
viet VVS came in February, 1971. That same
year, ight testing of the Ye-7BIS was conduc-
ted. Series production of the MiG-21BIS ran
from 1972 to 1985 at Factory No. 21 in Gor-
ky. A total of 2,013 units left this plant, and
it was the nal production version of the type,
which was made for the Soviet PVO and VVS,
and was also exported.