Aviation of Word War II
Light Transport Aircraft
Yak-6 - a light transport aircraft replaced the obsolete U-2, R-5 and P-Z biplanes. Their insufficient carrying capacity and range necessitated a new aircraft. The decision to build such a machine was made on April 26, 1942, and on September 8-16, state tests of the aircraft were already carried out at the Air Force Research Institute.
Construction. The Yak-6 was a twin-engine cantilever monoplane of an all-wood construction with a low wing position and a closed cockpit. Crew - 2 people. The trailing edge of the wing is straight, the leading edge is swept. The aircraft was designed for 190 hp M-12 engines, and the M-11 was installed due to the problems of the M-12.
Wing one-piece two-spar, with linen sheathing. An attempt to create a split wing led to an increase in the weight of the structure and had to be abandoned. In the center section, between the spars, there were gas tanks, in the tail section there was a landing flaps with manual control from a steering wheel with a cable drive.
Fuselage in its middle part - with plywood sheathing along the frame of four spars and a dozen frames, wide, with two pilot seats next to it. For the commander, a steering wheel is installed, for the right pilot - a control stick, cable wiring. The nose part of the fuselage is glued from veneer, the tail part is truss, four-spar, all the braces are pine bars, the linen sheathing is along a light frame made of stringers - slats. The canopy is folding, there is a door on the port side.
The stabilizer is two-spar, its angle of installation is adjustable on the ground.
Chassis tricycle with a tail wheel. The first copies and the prototype "NBB" had retractable OOSh with a manual drive and cable wiring. But in the future, the retractable chassis was abandoned - the gain in speed of 20 km / h turned out to be insignificant with an overall increase in weight and cost of the structure and the landing gear retraction mechanism was removed.
The powerplant consisted of two five-cylinder M-11F radial engines with a power of 140 hp each. This simple, cheap and reliable air-cooled motor was produced in large quantities and was used on many light aircraft developed in the USSR in the 1930s, including the Po-2, UT-1 and UT-2. Screw, wooden structure, fixed pitch 2.2 m diameter.
The power unit, including duralumin hoods, engine mounts, oil tanks and other units, was used from the UT-2 training aircraft. Two gas tanks with a capacity of 195 liters were made of plywood and covered with BF-2 glue for tightness from the inside and outside.
Equipment consisted of the standard flight and navigation equipment of the time. Air gyroscopes were powered by three Venturi tubes located on the starboard side of the cockpit. Lighting - a landing light in the nose fuselage fairing and ANO, which were powered by a 12A-30 battery.
In the modification Yak-6NBB , made in only one copy, the RSI-4 KV radio station and the RPK-10 radio compass were installed, powered by an electric generator driven by a windmill installed on the starboard side.
Behind the cockpit on the OP-102 pivot mount was a ShKAS machine gun (500 rounds) to protect against fighter attacks. To access it, a hatch with two duralumin doors was used.
On five MD-3-40 bomb racks in the center section (see diagram), up to five bombs of 100 kg were suspended, bombs up to 250 kg (no more than 2 pieces) could be installed on the middle three bomb racks. Provision was made for a suspension instead of bombs for pouring aviation devices 8V-116 for incendiary mixtures or chemical warfare agents. This modification of the aircraft was never put into production due to the low power of the power plant.
Insufficient engine power for a night close-range bomber turned out to be quite acceptable for its transport version as a command and communications aircraft. This option became the main one for the Yak-6 . In this version, the wing consoles were made detachable for ease of transportation by rail. The area of the ailerons was increased, the angle of the stabilizer was reduced and the angles of deflection of the rudders were increased, springs were introduced in the foot control, a large loading hatch was made on the starboard side (see photo).
Added a fuel tank, steel tanks, enlarged oil tanks, installed a common exhaust manifold for all cylinders. The empty weight of the aircraft increased by 47 kg, the armament was removed. The flight weight became 2300 kg (overload 2500).
The overall result of the serial production of the Yak-6 is 384 aircraft. By the end of 1943, the Air Force refused its supplies in favor of , which with the same engines could lift a much larger payload.