The Yakovlev Yak-1, a Soviet fighter aircraft utilized during World War II, possessed several notable characteristics.
This single-seat monoplane featured a composite structure and wooden wings, with production commencing in the early stages of 1940.
Renowned for its manoeuvrability, speed, and competitiveness, the Yak-1 proved to be an exceptional fighter aircraft.
Its composite-wooden structure facilitated ease of maintenance, while the engine exhibited remarkable reliability.
Moreover, this aircraft served as the foundation for subsequent advancements within the Yakovlev bureau, ultimately giving rise to a family of aircraft.
Notably, an impressive 43,000 units of the Yak-1 were constructed.
In recognition of his contributions, designer Alexander Yakovlev was bestowed with the prestigious Order of Lenin, a substantial prize of 100,000 Rubles, and a ZIS motor car.
Yakovlev, renowned for his light sports aircraft, gained recognition for his Yak-4 light bomber prior to the war.
The Soviet government was impressed and commissioned the OKB to develop a new fighter with a Klimov M-106 V-12 liquid-cooled engine.
The formal specifications, released on 29 July 1939, required two prototypes – I-26-1 with a top speed of 620 km/h (390 mph) at 6,000 m (20,000 ft), combat range of 600 km (370 mi), a climb to 10,000 m (33,000 ft) in under 11 minutes, and armed with 2 × 7.62 mm (0.300 in) ShKAS machine guns and 1 × 12.7 mm (0.50 in) Berezin BS heavy machine gun.
I-26-2 had a turbocharged M-106 engine with a top speed of 650 km/h (400 mph) at 10,000 m (33,000 ft) and armament of 2 × 7.62 mm (0.300 in) ShKAS machine guns.
The design capitalized on Yakovlev OKB’s expertise in sports aircraft, promising both agility and high-top speed.
Due to delays with the M-106 engine, the design was modified to incorporate the Klimov M-105P V-12 engine, with a 20 mm (0.787 in) ShVAK cannon mounted in the “vee” of the engine block.
On 13 January 1940, the inaugural flight of I-26-I took place, however, it encountered persistent issues with oil overheating that were never fully resolved.
Consequently, this led to a total of 15 emergency landings during the initial testing phase.
Tragically, on 27 April 1940, I-26-1 experienced a fatal crash resulting in the loss of its test pilot, Yu.I. Piontkovskiy.
The subsequent investigation into the accident revealed that the pilot had engaged in two consecutive barrel rolls at a low altitude, a clear violation of the designated test flight plan.
It was determined that during the first roll, the primary landing gear became disengaged, ultimately causing it to collide with the wing during the second roll.
Speculation arose suggesting that Piontkovskiy’s deviation from the flight plan may have been driven by his frustration over the fact that his aircraft was being utilized for engine testing, while I-26-2, which had been constructed with the knowledge gained from the unfortunate incident involving I-26-1, was already engaged in aerobatic manoeuvres.
The weight of I-26-2 was raised by 400 kg (880 lb) due to technical problems with sub-assemblies provided by different suppliers.
This increase in weight restricted the airframe to only 4.4 G, while oil overheating continued to occur, resulting in the aircraft failing government testing in 1940.
However, Yakovlev’s competitors, I-200 (future Mikoyan-Gurevich MiG-3) and I-301 (future LaGG-3), also failed testing.
The necessary improvements were made to I-26-3, which was delivered for testing on 13 October 1940.
Although it passed on 9 December 1940, the aircraft was still unfinished, with its engine problems remaining unresolved.
Soviet officials expressed concerns regarding the troublesome and slow testing and development processes associated with the I-26 aircraft, which was officially designated as the “Yak-1” on 19 February 1940, merely a month after its maiden flight as the I-26-1.
This decision was made in an attempt to minimize the time gap between the prototype phase and the commencement of production for operational aircraft.
Additionally, the I-200 and I-301 models were also authorized for production.
Despite being slower than the I-200 and less heavily armed than the I-301, the Yak-1 held an advantage due to its earlier initiation, which allowed for a consistent lead in testing and development compared to its competitors.
However, the onset of Operation Barbarossa, the Axis invasion of the Soviet Union on 22 June 1941, rendered the further development of promising designs, such as the Polikarpov I-185, unfeasible.
It is worth noting that Yakovlev, the designer of the Yak-1, may have enjoyed favouritism from Joseph Stalin, which could have influenced the Yak-1’s favourable position.
Simultaneous manufacturing and testing of a design that necessitated numerous enhancements, such as I-26, resulted in significant disruptions to the production process.
By 1941, approximately 8,000 modifications were made to the blueprints, followed by an additional 7,000 in the subsequent year and 5,000 more in 1942.
The scarcity of engines, propellers, radiators, wheels, and cannons further impeded production. Insufficient availability of high-quality materials led to the removal of plywood from the wings of several aircraft.
On 23 June 1941, Factory No.292, the primary producer of Yak-1s, was bombed and completely destroyed.
However, production recommenced amidst the ruins on 29 June.
Due to lose tolerances, each aircraft possessed unique characteristics, requiring workers involved in the final assembly to match dissimilar components.
The left and right main landing gear could differ in length and angle relative to the aircraft, necessitating adjustments to ensure a balanced stance.
Additionally, parts were often not interchangeable.
The production of Yak-1s ceased in July 1944, with an estimated total of approximately 8,700 units manufactured. Variants I-26
(Also known as Ya-26) The first prototype of the Yak-1 and progenitor of all Yakovlev’s piston-engined fighters of World War II. Of mixed steel tube and wood construction the lightweight I-26 displayed promising performance and was produced as the Yak-1. UTI-26 The third and fourth I-26s were completed as dual control trainers, produced as a fighter as the Yak-7. I-28 High-altitude interceptor prototype with Klimov M-105PD engine developed from I-26-2. Differed from I-26 in having an all-metal fuselage and tail and automatic, leading-edge slats on slightly smaller and reshaped wings. One aircraft was built, first flying on 1 December 1940. It did not enter production due to many engine deficiencies but served as the basis for high-altitude versions of Yak-7 and Yak-9. I-30 (Yak-3) Development of I-26 with an all-metal wing with leading-edge slats, weight and space savings were used for additional armament and greater fuel capacity. Two prototypes built – I-30-1 armed with 3 × 20 mm (0.79 in) ShVAK cannons and 2 × 7.62 mm (0.300 in) ShKAS machine guns, and I-30-2 with two additional ShKAS. It did not enter production. The name Yak-3 was re-used for a different fighter. Yak-1 Single-seat fighter aircraft. Initial production version. Yak-1b (“b” was an unofficial designation; after October 1942, all Yak-1s were built to this standard). New bubble canopy with lowered rear fuselage, increased armour, ShKAS machine guns replaced with a single 12.7 mm (0.50 in) Berezin UBS, electrical and pneumatic firing of the weapons instead of the mechanical system, new control stick based on the Messerschmitt Bf 109 design, new gunsight, airtight fuselage, retractable tailwheel, improved engine cooling, Klimov M-105PF engine with better low-altitude performance. The first flight (aircraft No.3560) took place in June 1942, with aircraft entering production in August. A total of 4,188 were built. Yak-1M Yak-3 prototype with a smaller wing, revised cooling intakes, reduced overall weight and upgraded engine. Two were built. Yak-7UTI Initial production version of the UTI-26. Yak-7 Conversions of Yak-7UTI and new production of fighter version of Yak-7UTI. There are various Yak-1 models that were not assigned specific names. These consist of experimental versions equipped with Klimov VK-106 and Klimov VK-107 engines, operational planes with the capacity to transport external fuel tanks, operational planes capable of carrying 6 × RS-82 rockets or 2 × 100 kg (220 lb) bombs, and lighter versions designed for air defence. Specifications Crew 1 Length 8.48 m (27 ft 10 in) Wingspan 10.0 m (32 ft 10 in) Height 2.64 m (8 ft 8 in) Wing area 17.15 m2 (184.6 sq ft) Airfoil Root Clark YH (14%) Tip Clark YH (10%) Empty weight 2,316 kg (5,106 lb) Max take-off weight 2,884 kg (6,358 lb) Powerplant 1 × Klimov M-105PF V-12 liquid-cooled piston engine, 940 kW (1,260 hp) at 700 m (2,300 ft) Propellers 3-bladed constant-speed propeller Performance Maximum speed 592 km/h (368 mph, 320 kn) at 4,900 m (16,100 ft) Range 700 km (430 mi, 380 nmi) Service ceiling 10,050 m (32,970 ft) Time to altitude 5.4 min to 5,000 m (16,000 ft) Wing loading 150 kg/m2 (31 lb/sq ft) Take-off run 340 m (1,120 ft) Landing run 560 m (1,840 ft) Armament Guns 1 × 20 mm (0.79 in) ShVAK cannon and 1 × 12.7 mm (0.50 in) Berezin UBS machine gun. Sources Yakovlev Aircraft Since 1924 – Bill Gunston & Yefim Gordon. OKB Yakovlev, A History of the Design Bureau and Its Aircraft-Yefim Gordon, Dmitriy Komissarov & Sergey Komissarov. Soviet Aircrafts Illustrated-A.S.Yakovlev.
The History of Soviet Aircraft from 1918-Vaclav Nemecek.
Soviet Combat Aircraft of the Second World War, Vol 1, Single Engine Fighters-Yefim Gordon and Dmitri Khazanov.
