In late 1941, Oleg Konstantinovich Antonov decided to create a hybrid of a tank and landing the glider, giving up a single power plant. Work on the glider, received the index of A-40 (or CT - wings of the tank), began in the most difficult period of the war - in December 1941 for the tests was provided by a serial light tank T-60.
Calculations showed that the undercarriage of the tank has sufficient strength and cushioning for the takeoff and landing. According to the concept design glider should be extremely simple and cheap in production design from nedefitsitnyh materials. Therefore adopted a long-known and well-proven scheme braced biplane with a wingspan of about 18 m. The two-spar wings, plywood with a sock to the first spar and fabric covering. Upper and lower wings connected by a system of four "I"-shaped struts and braces. Wings are equipped with slotted flaps, omitted in the landing 45 degrees down, which greatly reduces the landing speed. Office of the ailerons and flaps - cable runs on the lower wing and ailerons and flaps of the upper wing were associated with lower uprights streamlined section. On two box girder was attached dvuhkilevoe vertical tail, horizontal tail between them, too type biplanovogo system braces for rigidity. The elevator is only on the upper horizontal tail. Control surfaces are equipped with unguided trim and aerodynamic load compensators. Biplanovaya box of wings and tail boom were attached to the hull of the four points of the lower wing. Turning the handle, located on the right of the tank driver, who is also a pilot, fixed raskontrivalos and glider reset. Towing lock placed on the tank. To reduce the air resistance in flight tower for mounting a glider on a tank cannon ago unfolded. To improve visibility to the pilot-driver made a special optical device. Maximum estimated flight weight was 7.3 tons, the glider had 2 tons
Airframe manufactured in April 1942 in Tyumen, which was evacuated in size. Test A-40 began near Moscow in the Summer Research Institute (FRI) August 7, 1942 with jogging lightweight tank on a dirt airstrip and Betonka. In this objective was to find out whether the suspension will stand part of the machine speed 110-115 km / h (T-60 was 45 km / h). Were then made three reaching is "CT" to a height of 4 meters, which tested the control system.
First flight of "KT" was held on 2 September 1942, aircraft-towing-TB-3 with four reinforced (to 970 hp..) Engines AM-34RN commanded Paul Arsentievich Eremeev, formerly designer of aerobatic gliders. Glider ran a test pilot experimental test site of the airborne troops of the Red Army Sergey Anokhin. Due to the large mass and low circularity "KT" was conducted on the roadside close to the maximum engine power of the TB-3 with a speed of 130 km / h. Despite this, the rate of rise aeropoezda proved insufficient. The plane barely reached the height of 40 m.
Do not give a positive result of an attempt to increase the speed to 140 km / h, as this aeropoezd began to decline with the vertical velocity of 0,6 m / sec. In addition, the increase was the water temperature in the engine cooling system, which could lead to overheating. Under these conditions, Eremeev decided to withdraw aeropoezd area nearby airfield Bykov and unhook the glider. Anokhin, thanks to his professional skill, was able to successfully make a landing. After landing, he started the engine of the tank and not dropping wings, slowly moved toward the command post terminal. Without being warned about an unusual emergency landing apparatus, the head of airport operations on combat alert raised the calculation of anti-aircraft batteries. When a test pilot climbed out of the car, detained him, Red. The incident was settled with the arrival of rescue teams FRI. Tank under its own power delivered to the village of Stakhanov (now the city of Zhukovsky) to the airfield FRI. Thus ended the first and last flight of a flying tank.
In the act of testing a glider pilot pointed out the need to increase the trim of the elevator, setting steering control with worm gear and make constructive changes in the aerodynamic compensation to the aileron and flap control. It was noted that the task of creating a flying tank solved, but mistakes are made. Model glider and a tank for purging in the wind tunnel was performed in a simplified form (without cables connecting the biplane wing box and empennage, and without the simulation tracks the tank), which led to an error in the calculation of the aerodynamic properties of "quantum dots" and required power engine aircraft towing . Neuchteno air resistance, that does not allow the engine TB-3 to raise the glider at the desired height and complicate the management of in-flight.
Of the more powerful aircraft, capable of raising the air glider, "CT", armed at the time was a strategic bomber Pe-8 designs VM Petlyakova. However, during the war, built a total of 80 such machines. Pe-8 was used for in-depth air raids, in particular for the bombing of Berlin, and rely on its use as towing a glider "KT" was unreal.
Further flight tests winged tank stopped. Modification A-40
Wingspan, m 18.00
Length, m 12.06
Wing area, m2 85.80
maximum (with tank) 8200
Maximum speed km / h
Take-off speed, km / h 140
Landing speed, km / h 110
Payload One tank T-60