High Speed Day Bomber
The third version of the high-speed daytime bomber went under the designation "68", and in the Air Force - Tu-10. For some time the aircraft was designated as Tu-4, but then this name was given to the Soviet version of the American B-29. The 68 aircraft was a serial Tu-2 bomber with minor changes in the airframe, but with Mikulin AM-39FNV inline engines (direct injection) of 1,850 hp.
Having absorbed all the changes, the serial Tu-2 No. 16/20 in mid-May 1945 turned into an aircraft "68" 2 × AM-39 FNV. May 19, 1945 test pilot A.D. Perelet and lead test engineer B.N. Grozdov lifted the car into the air for the first time. Factory tests continued until June 8. The revealed defects were eliminated on the plane for a week, and on June 16 they passed the Air Force Research Institute for state tests. On November 17, "68", equipped with new AV-5LV-166B propellers, entered repeated state tests, which lasted until February 8, 1946.
In the Act of the Air Force Research Institute No. 17 for 1946, based on the results of repeated state tests of the "68" 2AM-39FNV aircraft with AV-5AV-166B propellers, it is concluded that "the aircraft can be recommended for service with the Air Force, provided that all defects noted in the act ".
The car was returned to the plant number 156 There, new AM-39 FN2 engines with four-blade AV-9K-22A vane screws and dust filters on the suction nozzles appeared on it, the vertical tail of an even larger area (6.03 m & # 178; instead of 5, 79 m & # 178;), tail wheel with pneumatic 530 × 230 mm. The transverse V of the wing was reduced by 15 degrees using tapered spacers along the docking station.
Pilot production finished all work on May 24. The first flight of the modernized "68" took place on May 28 (test pilot A.D. Perelet). The aircraft was also tested with AM-40 engines with four-blade AV-9K-22A propellers, but these engines did not give any advantages.
"68" 2 × AM-39FN2 (with AV-5LV-22A propellers) under the designation Tu-10 was launched into a small series at plant number 82. "68" embodied all the best for the machine of its purpose - high speed in combined with a significant bomb load, powerful defensive weapons and the necessary flight range. She became the last serial piston bomber of this class - the OKB was already working on jet aircraft.
Armament. Three defensive 12.7 mm UBT machine guns and two 20 mm ShVAK cannons in the wing roots; bomb load - 1000 kg, maximum - 3000 kg.