# Soko J-20 Kraguj

The Soko J-20 Kraguj (from Serbian: крагуј, lit. 'sparrowhawk') is a light military, single-engine, low-wing single-seat aircraft with a metal airframe, capable of performing close air support, counterinsurgency (COIN), and reconnaissance missions, that was designed by VTI and manufactured by SOKO of Yugoslavia, first flown in 1962.

## Design

It is of classic semi-monocoque, metal structure with a slightly tapered wing. The pilot is accommodated in an enclosed, heated and ventilated cockpit with adjustable seats. The cockpit canopy slides backwards to open. The landing gear is non-retractable with a tail wheel. Rubber dampers provide shock absorption, and hydraulic brakes are used for wheel braking.
The power plant comprises one 340 hp Textron Lycoming GSO-480-B1J6 piston engine and Hartzell HC-B3Z20-1/10151C-5 three-blade metal variable-pitch propeller. The engine cooling airflow is intensified by means of two specially designed ejectors. 36 US Gal of fuel contained in two rubber tanks enables a flight range of 350 NM for the fully armed configuration of the aircraft. 28 V DC electric power is supplied from a 1,5 kW generator and a storage battery. De-fogging and de-icing of the windshield is done by blowing of hot air.

### Armament

Permanent armament comprises two wing-mounted 7.7 mm Colt–Browning Mk II machine guns with 650 rounds each and a collimator sight in the cockpit. For combat missions there is a capacity for an external load of bombs and two 57 mm and two 128 mm (HVAR-5) air-to-ground rocket launchers. Adapters on the underwing pylons can be used to switch the armament configuration from free-fall bombs to multi-tube launchers with twelve 57 mm air-to-ground rockets. Cluster, bombs, cargo bombs, and 128 mm air-to-ground rockets can be fitted.

## Operation

Drawing on the nation's experience in WWII, Yugoslav military planners assumed that any potential aggressor would disable airfields early in the conflict. The Kraguj was therefore intended to provide a limited reconnaissance-gathering and strike capability to guerilla and insurgent groups in the event of the neutralization of the Yugoslav Air Force, and was referred to as a "Partisan aircraft". It was designed to operate from short, unprepared auxiliary airfields, especially in mountainous regions, and could be fitted with skis. In addition to its primary role as a ground support platform, it was also used as a trainer, both for basic visual day/night flight and for more advanced ground attack training.

## Former operators
### Croatia

* Croatian Air Force

### Republika Srpska

* Republika Srpska Air Force

### Yugoslavia

* SFR Yugoslav Air Force

## Specifications (J-20)

Data from Jane's All the World's Aircraft 1969-70
General characteristics
* Crew: 1
* Length: 7.93 m (26 ft 0 in)
* Wingspan: 10.64 m (34 ft 11 in)
* Height: 3.00 m (9 ft 10 in)
* Wing area: 17.0 m$^2$ (183 sq ft)
* Aspect ratio: 6:1
* Airfoil: NACA 4415
* Empty weight: 1,130 kg (2,491 lb)
* Max takeoff weight: 1,624 kg (3,580 lb)
* Fuel capacity: 240 L (53 imp gal; 63 US gal)
* Powerplant: 1 × Lycoming GSO-480-B1A6 6-cylinder air-cooled horizontally-opposed piston engine, 250 kW (340 hp)
* Propellers: 3-bladed Hartzell HC-B3Z20-1 constant-speed propeller, 2.44 m (8 ft 0 in) diameter
Performance
* Maximum speed: 295 km/h (183 mph, 159 kn) at 1,500 m (4,900 ft)
* Cruise speed: 280 km/h (170 mph, 150 kn) at 1,500 m (4,900 ft)
* Stall speed: 88 km/h (55 mph, 48 kn) (flaps down)
* Range: 800 km (500 mi, 430 nmi)
* Rate of climb: 8.00 m/s (1,575 ft/min)
* Take-off run to 15 m (50 ft): 189 m (620 ft)
* Landing run from 15 m (50 ft):: 324 m (1,063 ft)
Armament
* Guns: 2 × 7.7 mm Colt–Browning Mk.II machine guns (650 rounds each)
* Rockets: 2 × 12 round rocket pack or 6 × 57 mm or 127 mm rocket
* Bombs: 2 × 100 kg (220 lb) bombs