Bedunkovich P-3 (LIG-5) (Russian: Бедункович П-3 (ЛИГ-5)) light training aircraft was designed in 1936 as a development of the LK-4. The aim was to build a single model destined for aviation schools and which would be capable of covering all the stages of preparation of young military pilots in reconnaissance aircraft, biplane fighters and monoplanes. This was intended to lower operating and maintenance costs and reduce the number needed for training. This model was also known as LIG-5 according to the internal numbering of the Leningrad Civil Aviation Fleet Institute.
The change from one version to another was achieved by modifying the wing composition and quantity. The P-3 could be converted into three different versions of the trainer:
P-3 two-seater sesquiplane
Designed as a reconnaissance trainer, this version, due to its characteristics, was quite close to the Polikarpov R-5 reconnaissance biplane. A synchronized firing machine gun was installed on the aircraft through the propeller, an annular mount in the rear cockpit, and underwing mounts for four practice bombs. The cabin equipment included a radio station and a camera.
P-3 single-seat biplane
Designed as a biplane hunting trainer. This version was obtained by disassembling the upper center plane section together with the braces. The consoles of the upper wing were fixed one to the other and the braces were tensioned. A biplane box was obtained with the upper wing type parasol braced and the lower cantilever. The rear cabin was closing.
P-3 single-seater monoplane
Conceived as a monoplane hunting trainer. This model was obtained by eliminating the upper wing in the biplane configuration and replacing the tail empennage. You got an aircraft somewhat similar to the Polikarpov I-16.
The P-3 was designed as a two-seater tandem aircraft built primarily of wood. The powerplant selected was the 330 hp MG-31F engine.
The wing composition varied depending on the version. The wings were constructed of wood with a fabric covering. The cantilever-type lower plane featured trailing edge mechanization and was fixed in all versions. The upper wing was made up of a centroplane and two consoles braced by uprights that were shaped depending on the type of training.
With a detachable monoplane tail structure, it featured conventional type landing gear with tail skid and fixed main landings with aerodynamic fairings.
The construction of the prototype was developed in the workshops of the LII GVF. The aircraft was ready by the summer of 1936 and by February 1937 it had successfully passed factory tests. It was decided to carry out the state tests in Moscow, and airlift it to Moscow. During the flight and due to a pilot error, the plane had an accident in which it was destroyed. It was decided not to rebuild it.
P-3 in sesquiplan configuration
Powerplant: 330 hp MG-31F
Wingspan: 10.6 m
Wing area: 30 m²
Length: 7.5 m
Empty weight: 1100 kg
Maximum takeoff weight: 1560 kg
Fuel + oil weight: 220 kg
Maximum load capacity: 460 kg
Wing loading: 52 kg / m²
Power load: 4.73
Delivery weight: 29.5%
Maximum speed: 210 km / h
Landing speed 80 km / h
Autonomy: 3 h
Range: 500 km
Accommodation: 2
P-3 in biplane configuration
Powerplant: 330 hp MG-31F
Wingspan: 9 m
Wing area: 26 m²
Length: 7.5 m
Empty weight: 960 kg
Maximum takeoff weight: 1260 kg
Fuel + oil weight: 110 kg
Maximum load capacity: 300 kg
Wing loading: 48.4 kg / m²
Power load: 3.82
Delivery weight: 23.8%
Maximum speed: 220 km / h
Landing speed 75 km / h
Autonomy: 1.5 h
Range: 280 km
Accommodation: 1
P-3 in low wing monoplane version
Powerplant: 330 hp MG-31F
Wingspan: 9 m
Wing area: 14 m²
Length: 7.5 m
Empty weight: 850 kg
Maximum takeoff weight: 1150 kg
Fuel + oil weight: 110 kg
Maximum load capacity: 300 kg
Wing loading: 82 kg / m²
Power load: 3.49 kg / hp
Delivery weight: 26%
Maximum speed: 280 km / h
Landing speed 100 km / h
Autonomy: 1.5 h
Range: 300 km
Accommodation: 1
All Aero 