Yakovlev “Yak-3M”
Russian WWII single-engine single-seat monoplane fighter

Archive Photos

Yakovlev “Yak-3M” (N529SB, s/n 0470104) on display 8/27/2005 at the 2005 Camarillo Air Show, Camarillo, California (John Shupek photo)

Overview ²

The Yakovlev Yak-3 was a World War II Soviet fighter aircraft regarded as one of the best fighters of the war. As one of the smallest and lightest major combat fighters fielded by any combatant during the war, its high power-to-weight ratio gave it excellent performance.

Design and Development ²

The origins of the Yak-3 went Back to 1941 when the I-30 prototype was offered along with the I-26 as an alternate design to the Yak-1. The I-30, powered by a Klimov M-105P engine, was of all-metal construction, using a wing with dihedral on the outer panels. Like the early Yak-1, it had a ShVAK 20 mm cannon firing through the prop spinner and twin ShKAS 7.62 mm machine guns in the nose, but was also fitted with a ShVAK cannon in each wing. The first of two prototypes was fitted with a slatted wing to improve handling and short-field performance while the second prototype had a wooden wing without slats, in order to simplify production. The second prototype crashed during flight tests and was written off. Although there were plans to put the Yak-3 into production, the scarcity of aviation aluminum and the pressure of the Nazi invasion led to abandoning work on the first Yak-3 in the late fall of 1941.

In 1943, Yakovlev designed the Yak-1M which was a smaller and lighter version of the Yak-1. A second Yak-1M prototype was constructed later that year, differing from the first aircraft in plywood instead of fabric covering of the rear fuselage, mastless radio antenna, reflector gunsight and improved armor and engine cooling. The chief test pilot for the project Piotr Mikhailovich Stefanovskiy was so impressed with the new aircraft that he recommended that it should completely replace Yak-1 and Yak-7 with only the Yak-9 retained in production for further work with the Klimov VK-107 engine. The new fighter, designated the Yak-3 entered service in 1944, later than the Yak-9 in spite of the lower designation number. A total of 4,848 aircraft were produced.

The designation Yak-3 was also used for other Yakovlev projects - a proposed but never built, heavy twin-engine fighter and the Yakovlev Yak-7A.

Operational History ²

Lighter and smaller than the Yak-9 but powered by the same engine, Yak-3 was a very agile dogfighter and a forgiving, easy-to-handle aircraft loved by both rookie and veteran pilots. Early combat experience found it to be superior to all Luftwaffe fighters at altitudes below 5,000 m (16,400 ft). It could roll with the Focke-Wulf Fw 190 and its turn rate was far superior; a full circle in 18.6 seconds. The two biggest drawBacks of the aircraft were its short range and the tendency of the glued-on plywood covering the top of the wings to tear away under high-G loads. The pneumatic system for actuating landing gear, flaps and brakes, typical for all Yakovlev fighters of the time was also less reliable than the hydraulic or electrical systems, but it was preferred due to significant weight savings. The first 197 Yak-3 were armed with a single 20 mm ShVAK cannon and one 12.7 mm UBS machine gun, with subsequent aircraft receiving a second UBS for a weight of fire of 2.72 kg (6.0 lb) per second using high-explosive ammunition.

Variants ²

• Yak-3: Main production version
• Yak-3 (VK-107A): Klimov VK-107A engine with 1,230 kW (1,650 hp) and 2 × 20 mm Berezin B-20 cannons with 120 rounds of ammunition each. After several mixed-construction prototypes, 48 all-metal production aircraft were built in 1945-1946. In spite of excellent performance (720 km/h (447 mph) at 5,750 m (18,860 ft)), VK-107 was prone to overheating and it was decided to leave the engine for the better-suited Yak-9.
• Yak-3 (VK-108): Yak-3 (VK-107A) modified with VK-108 engine with 1,380 kW (1,850 hp), and armed a single 23 mm Nudelman-Suranov NS-23 cannon with 60 rounds of ammunition. The aircraft reached 745 km/h (463 mph) at 6,290 m (20,630 ft) in testing but suffered from significant engine overheating. Another Yak-3 with 2 × 20 mm Berezin B-20 cannons was also fitted with the engine with similar results.
• Yak-3K: Tank destroyer with a 45 mm Nudelman-Suranov NS-45 cannon, only a few built because Yak-9K was a better match for the weapon.
• Yak-3P: Produced from April 1945 until mid-1946, armed with 3 × 20 mm Berezin B-20 cannons with 120 rounds for the middle cannon and 130 rounds for each of the side weapons. The three-cannon armament with full ammunition load was actually 11 kg (24 lb) lighter than that of a standard Yak-3, and the one-second burst mass of 3.52 kg (7.74 lb) was greater than that of most contemporary fighters. Starting in August 1945, all Yak-3 were produced in the Yak-3P configuration with a total of 596 built.
• Yak-3PD: High-altitude interceptor with Klimov VK-105PD engine and a single 23 mm Nudelman-Suranov NS-23 cannon with 60 rounds of ammunition, reached 13,300 m (43,625 ft) in testing but did not enter production due to unreliability of the engine.
• Yak-3RD (Yak-3D): Experimental aircraft with an auxiliary Glushko RD-1 liquid-fuel rocket engine with 2,9 kN (650 lbf) of thrust in the modified tail, armed with a single 23 mm Nudelman-Suranov NS-23 cannon with 60 rounds of ammunition. On May 11, 1945, the aircraft reached 782 km/h (485 mph) at 7,800 m (25,585 ft). During the August 16 test flight, the aircraft crashed for unknown reasons, killing the test pilot V.L. Rastorguev. Like all mixed powerplant aircraft of the time, the project was abandoned in favor of turbojet engines.
• Yak-3T: Tank destroyer version armed with 1x 37 mm Nudelman N-37 cannon with 25 rounds and 2 × 20 mm Berezin B-20S cannons with 100 rounds each. Cockpit was moved 0.4 m (1 ft 4 in) Back to compensate for the heavier nose. Engine modifications required to accept the weapons resulted in serious overheating problems which were never fixed and the aircraft did not advance beyond the prototype stage.
• Yak-3T-57: Single Yak-3T with a 57 mm OKB-16-57 cannon
• Yak-3TK: Powered by a VK-107A engine, and fitted with an exhaust turbocharger.
• Yak-3U: Yak-3 fitted with Shvetsov ASh-82FN radial engine with 1,380 kW (1,850 hp) in an attempt to increase performance while avoiding the overheating problems of VK-107 and VK-108. Wingspan increased by 20 cm (8 in), wings moved 22 cm (9 in) forward, cockpit raised by 8 cm (3 in). Armament of 2 × 20 mm Berezin B-20 cannons with 120 rounds per gun. The prototype reached 682 km/h (424 mph) at 6,000 m (19,680 ft) and while successful did not enter production because it was completed after the war.
• Yak-3UTI: Two-seat conversion trainer based on Yak-3U powered by Shvetsov ASh-21 radial piston engine. The aircraft became the prototype for the Yak-11.

Operators ²

• France: Normandie-Niemen squadron
• Poland: Air Force of the Polish Army
• Soviet Union: Soviet Air Force
• Yugoslavia: SFR Yugoslav Air Force

Modern Recreations ²

In addition, since 1991, a number of Yak-3s have been newly manufactured by Yakovlev for the warbird market using the original plans and dies. These are powered by Allison V-1710 engines and have the designation Yak-3M. Several of these are airworthy today, mostly in the United States, but also in Germany and Australia. Others have been converted to "Yak-3" status from Yak-11 trainers (with the fitting of a Allison engine) for private owners, with these aircraft also being very popular worldwide.

Specifications and Performance Data ^{3, 4}

General Characteristics

• Country of Origin: Russia
• Type: Single-seat fighter
• Manufacturer: Yakovlev Design Bureau
• Crew: One

Wings

• Low-wing cantilever monoplane.
• Two half wings attached to a center-section which forms part of the fuselage and floor of cockpit.
• Low aspect ratio.
• Thin airfoil.
• Tapered leading and trailing-edges.
• Dihedral from wing roots.
• Air intake in leading-edge at each wing root.
• Structure consists of two spars of extruded metal, wood ribs and skin of fabric over plywood, varnished and lacquered.
• Fabric-covered ailerons with trim-tabs on correct that trailing-edge.

Fuselage

• Framework of welded steel-tubing, covered by two half-shells of what attached to tubular framework by webbing bands.
• This also fabric-covered and lacquered.

Tail Unit

• Cantilever monoplane type.
• All-wood tailplane and fin.
• Fabric-covered elevators and rudder.
• Trimming-tabs in elevators and as extension on rudder.

Landing Gear

• Tail-wheel type.
• Main wheels retract inwards into wing roots.
• Tailwheel retracts into rear fuselage.
• Oleo pneumatic shock-absorbers.
• Messier type brakes on main wheels.

Power Plant

• No. Engines: One
• Manufacturer: V. Y. Klimov
• Engine Designation: VK-105PF-2, V-12 liquid-cooled piston engine
• Power: 962 kW (1,290-hp)
• Power/mass: 0.36 kW/kg (0.22 hp/lb)
• Metal three-blade variable-pitch non-feathering Hamilton type airscrew.
• Coolant radiator under fuselage just aft of cockpit.

Accommodation

• Enclosed cockpit for pilot.
• Long flat cockpit cover with sliding hood forming center part.

Armament

• One Sh-VAK 20 mm motor cannon.
• Rate of fire 600-800 rounds per minute.
• 150 shells.
• Two Beresin 12.7 mm machine guns mounted in cowling.
• Rate of fire 800-1000 rounds per minute.

Armor

• 7 mm steel-plate behind seat.
• 4 mm steel-plate at sides.
• Rear of cockpit cover 6 mm bullet-proof glass.
• No protection above or below.

Dimensions

• Wingspan: 9.2 m (30 ft 2 in)
• Length: 8.5 m (27 ft 10 in)
• Height: 2.39 m (7 ft 11 in)
• Wing Area: 14.85 m² (159.8 ft²)

Weights

• Empty Weight: 2,105 kg (4,640 lb)
• Loaded Weight: 2,692 kg (5,864 lb)
• Wing Loading: 181 kg/m² (36.7 lb/ft²)

Performance

• Maximum Speed: 646 km/h (401 mph)
• Rate of climb: 18.5 m/s (3,645 ft/min)
• Service ceiling: 10,700 m (35,000 ft)
• Range: 650 km (405 miles)

References

1. Photos: John Shupek
2. Wikipedia, the free encyclopedia, https://en.wikipedia.org/wiki/Yakovlev_Yak-3
3. Bridgman, Leonard, Grey, C. G., Jane's All the WorlD’s Aircraft 1949/50, Sampson Low, London, England, 1950
4. Green, William and Swanbourough, Gordon, The Complete Book of Fighters, Smithmark Publishers Inc., New York, NY, 1994, ISBN 0-8317-3939-8