The Polikarpov NB, also known as the Night Bomber, was an aircraft developed by the Soviet Union during World War II.
Unfortunately, the project was cut short after the death of Nikolai Nikolaevich Polikarpov, the chief designer of the aircraft, in 1944.
Despite its potential, only one prototype of the twin-engined bomber was ever constructed before the program came to an end.
The NB program’s origins are shrouded in mystery, but the design process commenced in the winter of 1941-42 with the OKB designation of the T aircraft.
The NB was a monoplane with a high-wing configuration, featuring twin engines and twin tails.
Its construction involved a combination of materials, with the fuselage made of moulded birch plywood known as ‘shpon’, measuring 4-5 mm in thickness.
To enhance its structural integrity, the fuselage was reinforced with a welded steel tube framework and a network of bracing wires in the midsection, specifically around the wing aperture and the spacious bomb bay.
The wing, which had a single-spar design, was constructed using a mixture of steel and duralumin.
While the center section was covered with duralumin skin, the outer panels were skinned with ‘shpon’.
The wing’s length was divided by the engine nacelles, with electrically powered duralumin slotted flaps running along the wing centre section.
Additionally, automatic leading-edge slats were mounted on the outer panels.
All control surfaces were crafted from wood and covered with fabric.
The tailplane, featuring twin fins and a 7° dihedral angle, was also made of duralumin and covered with ‘shpon’.
In terms of landing gear, the NB employed a conventional undercarriage system.
The main gears retracted aft into the rear of the engine nacelles, while the tail wheel retracted into the rear fuselage.
The aircraft housed a total of six protected fuel tanks in the wing centre section, along with four additional tanks in the outer wings.
These tanks had a combined capacity of 2,760 kg (6,085 lb), including oil.
The NB was powered by two air-cooled Shvetsov ASh-82 radial engines, each generating 1,379 kW (1,849 hp).
Although alternative engines such as the Mikulin AM-39 V-12 and the Shvetsov M-71 radial were considered, development issues led to their exclusion from further consideration.
The nose of the aircraft was designed with a significant amount of glass, providing the bombardier with a wide field of vision.
Additionally, the nose housed a fixed 12.7 mm (0.50 in) Berezin UB machine gun, equipped with a reflector sight for the pilot’s use.
Moving towards the rear, a turret was installed for the dorsal gunner, who operated a UBT machine gun.
Furthermore, a hatch allowed the ventral gunner to fire another UB machine gun.
In terms of its payload capacity, the bomb bay had the capability to internally carry up to 2,000 kg (4,400 lb) of bombs, while an additional 3,000 kg (6,600 lb) could be mounted underneath the wings.
On 23 May 1944, the NB aircraft successfully completed its inaugural flight, followed by the manufacturer’s flight tests in August.
The aircraft showcased exceptional performance capabilities, demonstrating great promise.
However, the unfortunate demise of Polikarpov, the designer, occurred a month prior to these achievements.
Consequently, his design bureau was forced to cease operations, leading to the termination of all ongoing projects under his supervision. Specifications Crew 5 Length 15.29 m (50 ft 2 in) Wingspan 21.52 m (70 ft 7 in) Wing area 58.1 m2 (625 sq ft) Airfoil NACA-230 Empty weight 8,843 kg (19,495 lb) Gross weight 13,800 kg (30,424 lb) Fuel capacity 2,760 kg (6,085 lb) (including oil) Powerplant 2 × Shvetsov ASh-82FNV 14-cylinder radial engines, 1,379 kW (1,849 hp) each Propellers 3-bladed Performance Maximum speed 510 km/h (320 mph, 280 kn) at 5,000 m (16,400 m) Range 3,030 km (1,880 mi, 1,640 nmi) with 3,000 kg (6,614 lb) of bombs Service ceiling 6,150 m (20,180 ft) Time to altitude 12 minutes to 5,000 metres (16,404 ft) Armament Guns 3x 12.7 mm Berezin UB machine guns Bombs Up to 5,000 kilograms (11,023 lb).
