The Yak-7B

The Yak-7 started as a trainer for the Yak-1 in January, 1940, and took to the air for the first time in July 1940. Changes in the Yak-1 and Yak-7 took place simultaneously. Movement of the center of gravity further aft avoided nose-overs on landing. Changes in air intakes addressed engine overheating. The re-designation from Yak-1UTI to Yak-7 occurred officially in February 1941.

With the German invasion of the Soviet Union, the Soviet Air Force decided to turn the Yak-7 into a tactical fighter in August 1941. The rear cockpit was removed and covered over. New armament included a 20 mm cannon firing through the propeller boss, and two 7.62 mm machine guns. Six rocket launch rails were installed under the wings. Production began in September 1941, but factory movement to Siberia in October 1941 limited production numbers. The Yak-7 entered combat in defense of Moscow in December 1941.

The Yak-7A powered by the Klimov M-105PA completed acceptance trials with wheels or retractable skis in early 1942. This variant deployed to the Vokhov and Western Fronts in early summer 1942. Combat pilots complained about poor rearward visibility, inherent in both the Yak-1 and Yak-7 aircraft, due to the “razor-back” configuration. A “bubble” canopy was suggested.

The Yak-7B was equipped with increased armament: one 20 mm cannon and two 12.7 mm machine guns. Rocket rails were provided for six unguided rockets. An alternative underwing load was provision to carry two 25 to 100 kilogram bombs. The rocket rails were deleted in May 1942. One in ten aircraft carried a two-way radio.

The heavier armament added to the aircraft moved its center of gravity forward aggravating its inclination to nose over on landing. In compensation an 80 liter fuel tank was added in the rear cockpit. Combat pilots objected to the fuel tank in the cockpit and fighter units at the front tended to remove the tank.

Designers increased the boost pressure of the M-105PF increasing the horsepower from 1,050 to 1,180 hp. This required a modification of the fine pitch on the propeller to access the power. A Yak-7B weight reduction program included lightening the airframe, deleting the wiring for the rockets, and deleting the 80 liter fuel tank.

The Yak-7B entered combat in the summer of 1942, engaging in intense battles over Stalingrad. In one engagement on 20 August Soviet pilots claimed 29 German aircraft shot down for a loss of nine.

An Air Force study of the performance of the Yak-7B revealed that many pilots flew the aircraft with the canopy either open, or removed. Radiator and oil cooler shutters were open, and wheel doors and maintenance access panels were poorly fitted. Pilots operated the engine at a reduced setting of 2,700 rpm resulting in speed reductions of 40 to 50 km/hr.

Aircraft produced at the Moscow plant, as opposed to the plant at Novosibirsk, were of lower quality resulting in speed losses of 25 to 30 km/hr, higher stick forces, and more sluggish maneuverability. Poor production standards or faulty installation resulted in machine gun failures in the Yak-7B. Flawed design of shell ejection chutes and feed sleeves contributed. Cannon failures were caused by poor design of the case ejector chutes and the belt link collectors. Low grade substitutes of various chemicals in the bonding glue resulted in defective bonding of the wooden skin to the internal structure causing the skin to rip away in flight.

Later improvements to the Yak-7B included cutting down the upper rear fuselage and fitting a bubble canopy. Emergency canopy jettison devices were installed. A combined throttle and pitch control, introduced in 1943, reduced pilot work load in combat situations.

Production of the Yak-7B continued to July 1944 with 5,120 being built. The aircraft remained in service to the end of the war, and proved tough enough to take considerable damage in battle and still return safely.

Source: Yakovlev Fighters of World War Two, Yefim Gordon, Sergey Komissarov and Dmitriy Komissarov, Hikoki Publications, Manchester, England, 2015


The Yak-1 in Combat

The Soviets and the Germans had very different ways of determining the effectiveness of a fighter in combat. The Germans, just like we in the United States, view the success of a fighter by the performance and the kill/loss ratio. For the Soviets in the Great Patriotic War, the effectiveness of a fighter was determined by its ability to assist the advance of the forces on the ground, and its ability to protect attack aircraft from enemy air attempts to disrupt Soviet air support effectiveness.

The Yak-1 entered service shortly before the German attack on the Soviet Union: Operation Barbarossa. It remained in service throughout the war. Even as late as December 1943 Yak-1s were still provided as replacement aircraft to units in active combat against German forces. Improvements of the aircraft continued throughout the production run, taking place on the assembly line, or in the field. Modifications of the aircraft tended to increase the weight of the aircraft, negatively affecting its performance so work continued to find ways to increase the power of the engine, improve the efficiency of the propeller, reduce the aircraft weight, and aerodynamic and parasitic drag.

Rocket tubes under the wings, 37 mm cannon, increased rate of fire in the 20 mm cannon were all tried. Self-sealing fuel tanks, inert gas pressurization systems for the fuel tanks, armored glass for the windscreen, dust filters to protect the engine, modified exhaust stubs to provide additional thrust, increased the safety and usefulness of the aircraft.

During the initial battles against German forces the majority of Yak-1s in the Western and Southwestern fronts were destroyed, primarily on the ground. The aircraft was new to the crews and the pilots had not yet learned how to use them. In spite of this, one unit in three days in June 1941, destroyed 26 enemy aircraft on the approaches to Kiev.

Yak-1s were used in the early days, primarily in the air defense of Moscow. Unusually, they were also used to strafe advancing German ground troops. Their numbers increased as the year advanced. By the end of 1941 the Yak-1s were being joined by Yak-7s. Production of the Yak-1 ended in July 1944.

During the battle for the Kursk Salient 659 Yak-1s and Yak-7Bs served with the Second and the Sixteen Air Armies. Yak-1s took part in the 1944 Belorussian Strategic Offensive Operation, which destroyed the German Army Group Center, by protecting ground attack aircraft supporting Soviet troops. By this time the Yak-9 began to replace the Yak-1s and Yak-7s, although these were still providing reconnaissance services.

Some of the greatest Russian aces began their careers flying Yak-1s, including Aleksandr I. Pokryshkin with 53 personal kills and six shared kills.

Source: Yakovlev Fighters of World War Two, Yefim Gordon, Sergey Komissarov, and Dmitriy Komissarov, Hikoki Publications Ltd, Manchester, England, 2015


As the most produced fighter series in history, the significance of the Yakovlev fighters cannot be overestimated. As mentioned in one of my previous blogs, at the beginning of the Great Patriotic War in June, 1941, only one tenth of the Soviet fighter force consisted of Yak-1s, and the most numerous modern fighter in the Soviet inventory was the Mig-3.

The Yakovlev fighter series began as the I-26, entered in the fighter competition with three other Yak prototypes. The I-26 was presented as a low and mid-altitude tactical fighter of mixed aluminum, and wood and fabric construction. It performed well at the prototype trials, achieving a maximum speed at sea level of 490 kilometers per hour and 585 kilometers per hour at 4,800 meters. The pilots reviewing the prototype found it easy to handle, though aerobatics were limited because of g load restrictions. The aircraft failed its state trials because of a laundry list of design and manufacturing flaws.

Many of the flaws were corrected before five prototype aircraft began operational trials. Production began at a Moscow factory in autumn 1940. At the time of the German invasion the Moscow plant was producing three aircraft per day. These aircraft were initially based at airfields near Moscow.

In combat the Yak-1 proved to be the best of the Soviet fighters, but its main opposition, the Bf 109F-2 and F-4 variants, were superior. In particular the Bf 109F-4’s speed advantage allowed it to engage in or break off combat at will.

In an effort to improve the Yak-1’s performance it was equipped with a Klimov M-105 PA engine. Although this did not eliminate the Yak-1’s inferiority to the Messerschmitt fighter, the new engine allowed prolonged inverted flight as well as negative g dives.

The first 1,000 Yak-1s were not equipped with radios. Future machines were equipped at a ratio of one in ten.

With the onset of winter the Yak-1, like all other Soviet combat aircraft, were painted with a chalk like white coating for camouflage. Skis on the Yak-1s allowed operation from snow covered fields. Large motorized rollers were used to flatten the snow prior to takeoff.

It is my intention to provide a developmental history of the Yakovlev series fighters and an outline of their operations during the Great Patriotic War. I also intend to discuss the careers of a number of the aces who flew these machines, including the exploits of the women who flew this machine in combat.

Sources: Soviet Combat Aircraft of the Second World War, Volume One: Single-Engined Fighters, Yefim Gordon and Dmitri Khazanov, Midland Publishing Limited, Leicester, England, 1998

Yakovlev Fighters of World War Two, Yefim Gordon, Sergey Komissarov, and Dmitriy Komissarov, Hikoki Publications, Ltd., Manchester, England, 2015


Pawn of the Soviet Air Force–the Pe-2

The Soviet Union’s premier twin-engine attack bomber was the Pe-2, also known as Peshka, the Pawn. Designed by Vladimir Petlyakov, the Pe-2 was put in production in 1940. More than 450 had been produced by the time of the German attack on Russia in the summer of 1941, however, only only a few dozen aircraft were operational.

Originally powered by a pair of Klimov M-105-R engines the aircraft had a top speed of 445 kilometers per hour at sea level. Initial offensive armament was a 12.7 mm machine gun on the starboard and a 7.62 mm machine gun on the port side of the nose. Initial defensive armament was a rearward firing 7.62 mm flexible machine gun fired by the navigator from the rear of the cockpit canopy. The ventral gun, also a 7.62 mm weapon, was aimed by the gunner, alone in the middle of the fuselage, using a periscopic mechanism attached to the gun mount. In the field some units installed flexible 7.62 mm machine guns firing through portholes in the sides of the fuselage just behind the wing root.

Maximum bomb load was 1,000 kilograms. Normal bomb load was 600 kilograms. Four 100 kg bombs could be carried on mounts in the internal bomb bay. Initially a 100 kilogram bomb could be carried in each engine nacelle behind the landing gear. These were ultimately closed off. The external bomb load was carried under the wing center section between the engines: four 250 kilogram bombs, or two 500 kilogram bombs.

In 1942 experiments were conducted using the Pe-2 as a dive bomber. Using the extendible slatted speed brakes outboard of the engines the Pe-2s would dive at a 70 degree angle in line astern, spaced at 500 to 600 meters. After each aircraft dropped its bombs the attackers would form a ‘carousel’ keeping the target under constant attack. Fighters established a high cover over the bombers with two or three fighters diving with the bombers to provide support.

German pilots flying the Bf 109E found it difficult to catch the speedy little dive bomber. Later German fighters, with higher powered engines and greater speed potential could catch and down the Pe-2. As a result, aircrews complained about weak armament and insufficient armor plate protection for the ventral gunner. The 7.62 mm defensive guns were replaced with heavier caliber 12.7 mm weapons and armor protection for the navigator/rear gunner and the ventral gunner was extended. This change affected the speed of the aircraft which required a power plant change to the M-105-PF. The 130 horsepower increase allowed the Pe-2 to reach 460 kilometers per hour at sea level in a clean condition. The increased weight of the weaponry, armor, and external mounting of the bombs compromised the speed under operational conditions. and the pilots of the Bf 109Fs and Gs took notice of the increased caliber of the defensive weapons.

The Pe-2 had a reputation for difficult handling and inexperienced pilots found it impossible to land with one engine out. It proved demanding but not impossible to fly.

Sources: Soviet Combat Aircraft of the Second World War: Volume Two: Twin-Engined Fighters, Attack Aircraft and Bombers, Yefin Gordon and Dmitri Khazanov with Alexander Medved, Midland Publishing Ltd., Leicester, England, 1999

Profile 216: Petlyakov Pe-2, Malcolm Passingham and Waclaw Klepacki, Profile Publications Ltd., Windsor, England, 1971


The Il-2: Russia’s “Flying Infantryman”

“Our army needs Il-2s as much as it needs bread, as much as it needs the air it breathes.” Joseph Stalin.

As the world’s first practical armored attack aircraft, Ilyushin’s Il-2 Shturmoviki made up a third of the USSR’s combat aircraft fleet during the Great Patriotic War–known to the West as World War II. Central to its construction was the one-piece armored bath with integrally pressed engine bearers and cooler nests. This thirteen mm thick armor plate extended from the nose to the rear of the cockpit and was augmented by armored glass for the canopy and 55 to 65 millimeter armored glass windscreen. It could not be penetrated from below by low caliber projectiles. Main undercarriage wheels were semi-exposed when the gear was retracted to allow gear up landings with minimal structural damage to the aircraft.

In a study done by the Soviet Union during the war, this aircraft’s only weak points were the wooden rear fuselage, the wooden outer wing panels, and the oil radiators. Metal outer wing panels proved to be more survivable.

Powered by an AM 38 engine of 1,680 horsepower and armed with two Shkas 7.62 mm machine guns, two Shvak 20 mm cannon, rails for eight 82-mm RS 82 rockets and a bomb capacity of 400 kg, 249 single-seat Il-2s were in service at the time of the German attack. With a fighter escort flying at 1000 to 1500 meters altitude and the Il-2s gliding down to attack at 10 meters altitude, Soviet pilots complained that the aircraft was vulnerable to attack from behind by fighters firing at ranges of 10 to 15 meters. By the summer of 1942 pilots frequently carried only half a bomb load, if they carried bombs at all. Their attacks were frequently made with guns and rockets alone. They recommended the addition of a rear gunner.

Two-seat Il-2s began to appear at the front in the spring of 1942, and the Il-2m3 made its appearance in August 1942. The armor plating was lengthened to include the rear gunner with minimal structural changes. Initially the rear gunner was provided with a pair of 7.62 mm machineguns. This was altered to a 12.7 mm machinegun. The pilot’s armament was increased to two 23 mm cannon in the wings. The Soviet Air Force now mandated a minimum 400 kilogram bomb load.

Experiments with 37 mm cannon were also conducted and small numbers were available at Kursk. The powerful recoil of these cannon made aiming difficult.

In January 1943 the AM 38F engine was introduced. This engine was uprated to 1,750 horsepower and was able to use low octane fuel. At the Battle for Stalingrad in the winter of 1942/43, 1,644 Il-2s were available. By the time of the Battle for the Kursk Salient, in July 1943, that number increased to 2,817 Il-2s.

German fighter pilots quickly learned that the Il-2 pilot’s standard attack procedure was to glide from 1,000 to 1,500 meters altitude to their attack altitude of 10 meters and then to turn to port to set up the Circle of Death. This technique allowed the Shturmoviki to have aircraft over the target continuously for an extended period. During the Battle for Kursk the 9th Panzer Division lost 70 tanks in 20 minutes on 7 July, 1943. German pilots took advantage of the knowledge of the port turn to set up their attacks. Even so, the Germans found the Il-2 difficult to down when it was evading at 10 meters altitude and 400 kilometers per hour.

Although we have no knowledge of all women Il-2 units, we do know that many of the units had mixed aircrews.

Sources: Soviet Combat Aircraft of the Second World War Volume Two: Twin-Engined Fighters, Attack Aircraft, and Bombers, Yefim Gordon and Dmitri Khazanov with Alexander Medved’, Midland Publishing Ltd., Leicester, England, 1999

The Ilyushin Il-2, Number 88, Witold Liss, Profile Publications Ltd. Leatherhead, England.


The Yak–The Soviet Union’s Premier Fighter

Prior to the Second World War most Soviet fighters were biplanes. The sole exception before 1940 was the Polikarpov I-16, the first cantilever wing monoplane fighter with retractable landing gear in the world. As the war in Europe began the Soviet government realized that their air force equipment lagged behind that of Germany and the aircraft designers were encouraged to develop new designs. New engines such as Vladimir Klimov’s M-105 inspired Aleksandr Yakovlev’s design of the I-26, prototype of the Yak series of aircraft. The M-105 had a hollow drive-shaft which allowed the fitting of a 20 mm cannon mounted on the engine which could fire through the propeller hub, unrestricted by the rpm of the engine.

Designed with a steel truss forward fuselage and a wood and fabric rear fuselage and a one piece wooden wing, the Yak-1 entered service with test squadrons in 1940. By the time of the German blitzkrieg into Russia, Operation Barbarossa, only 100 Yak-1s were in service on the western frontier. The majority of fighters in the Soviet Air Force were I-15 biplanes and the I-16 mentioned above. Of the modern fighters absorbing the initial German assault, the most numerous was the MiG-3 – 886 of the 980 modern fighters on the front. The remainder were Yak-1s and LaGG-3s. By 1 May, 1942, there were 134 MiG-3s in inventory of which 3/4 were combat capable. The MiG-3 was a difficult aircraft for new pilots to fly, in part due to the aft center of gravity. Additionally, the Germans targeted these modern aircraft. Due to poor performance in combat production of the MiG-3 ended in December 1941.

When the Wehrmacht invaded the Soviet Union in June 1941 only one tenth of the Soviet fighter force were Yak-1s. Initially pilots considered the Yak-1 to be too delicate for combat, but the Luftwaffe pilots considered the Yak the best Soviet fighter at the time. Constant improvement of the aircraft over the first six months of the Soviet involvement of the war caused the Soviets to conclude that, in spite of the many defects in the Yak-1, the defects were not as damaging as those in the MiG-3 or the LaGG-3. Development of winterized Yak-1s began in autumn of 1941 allowing more than 800 to be available in February 1942.

The Yak-1B, with improved pilot vision, armament and armor, was available in June 1942. The development of the Yak-7 began in August 1941, and the first combat action took place during the Soviet offensive at Moscow in the winter of 1941/42. Production of the Yak-9, the definitive aircraft of the series, began in October 1942 and was first used in combat during the counter-attack at Stalingrad in December 1942.

All three variants of the Yak fighter engaged in combat during the battle for the Kursk Salient. Although less sophisticated than the P-51 Mustang and less combat damage resistant than the Bf 109 or the Fw 190, they were perfect for the use to which they were put: close support of the ground forces. In combat at medium and low altitudes these aircraft were a match for any opponent. By the end of the war more than 35,000 of these machines of all variants had been produced and their service record was outstanding.

Sources: Yakovlev Fighters of World War Two, Yefim Gordon, Sergey Kosissarov, Dmitriy Komissarov, Hikoki Publications, Manchester, England, 2015; Soviet Combat Aircraft of the Second World War: Single Engine Fighters, Yefim Gordon and Dmitri Khazanov, Midland Publishing Limited, Leicester, England, 1998; The Soviet Air Force in World War II: The Official History, Edited by Ray Wagner, Translated by Leland Fetzer, Doubleday & Co., Inc., Garden City, NY, 1973