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Overview
In the mid-1960s, the Ilyushin OKB were tasked with designing a successor
to the Antonov An-12 "Cub", a medium range turboprop transport
with good rough field capability. This new aircraft would have to possess twice the range and
payload of the earlier type without suffering any loss in field performance, a many-wheeled chassis
with high cross-country capacity together with the powerful mechanization of wings and high power
capacity to make it possible for the plane to takeoff from unprepared dirt airstrips, and also have
the ability to transport an 88,185 pound (40 metric ton) load over 3,100 miles (5,000km) in under six
hours, at a lower cost than the An-12BP would be able to achieve.
The basic layout, conceived in 1967, was indeed similar to the U.S.-built
Lockheed C-141A Starlifter, but the new design had a larger cargo hold area and more powerful
engines to achieve the desired performance. Over thirty international patents were obtained
for the design, and the OKB later claimed that 180 new inventions were incorporated into the
aircraft.
The first Ilyushin Il-76 (SSSR-86712) flew on 25 March 1971 and was the subject of
an abbreviated test program. The aircraft made its public debut at Sheremetyevo Airport on 18 May
1971, much to the surprise of Western observers and flew to Paris the next week.
In July 1975, a pre-production Il-76 established 25 new payload to altitude
records during four test flights, 24 of which were later ratified by the FAI. They included lifting
a payload of more than 154,590 pounds (70 metric tonnes) to an altitude of 38,960 feet (11,875m),
and a speed of 532.33 mph (856.7km/h) around a 1,080 nm (2,000km) closed circuit with 121,253 pounds
(55 metric tonnes). Operating mainly as a civilian passenger/cargo transport for Aeroflot, it had
not escaped Western eyes that the aircraft would be an important reserve to those surely operated
by the military, and indeed this was the case.
The military version differed by having four ECM fairings on the nose,
different avionics plus a rear gun turret, mounting two twin barreled 23mm cannons. (Il-76s
operating in Afghanistan were also fitted with flare dispensers.)
The cargo hold is fully-pressurized and has a titanium floor with fold-down
roller conveyors, and can be quickly reconfigured by using interchangeable passenger, freight or
air ambulance modules. Somewhat larger than that available in the C-141A, it can accommodate 125
fully-equipped paratroops.
Loading is accomplished using two internal overhead winches, each of which can
use two 6,615 pound (3,000kg) or four 5,511 pound (2,500kg) hoists. The ramp itself can be used as a
lift, with a capacity of up to 66,150 pounds (30,000kg). The hold is compatible with international
standard containers and pallets.
The Il-76MD variant has an increased flight range and service life. The powerplant
and systems are identical to those of the Il-76M and the structural changes have been made to its
airframe only to accommodate the increased service life and increased takeoff weight. When operating
from first-category concrete runways, the aircraft's takeoff weight has been increased from 170 tons
for the Il-76M to 190 tons for the Il-76MD, mainly due to the increased fuel. This enables a flight
range increased by 40% with a maximum payload. The Il-76MD can be operated from unpaved runways in
forward areas of operation.
The Il-76MF aircraft is a derivative of the Il-76MD, with the fuselage lengthened
by 21 feet, 8 inches (6.6m). The new PS-90A-76 engines give a 25% higher takeoff thrust than the
D-30KP engines on the MD variant. The flight range is increased by over 20%, for example the flight
range with a 40 ton payload is 3,132 nautical miles (5,800km), compared to a range of 2,592 nautical
miles (4,800km) for the Il-76MD.
Since 1971, more than 700 Il-76 airframes have been produced. Several Il-76 variants exist, including the Il-78 "Midas" and a firefighting aircraft capable of
carrying 42,000 liters of retardant.
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