Aviation of World War II
Pe-3 - a two-seat fighter, interceptor, bomber and photo reconnaissance - a modification of the serial Pe-2. Leaving the scheme, dimensions and basic equipment unchanged, the designers equipped the wing of the aircraft in the version of the fighter-interceptor with automatic slats. In accordance with the new purpose of the aircraft, much attention was paid to increasing the duration and range of the flight. The wing of the base Pe-2 contained a total of 8 gas tanks, which could not be significantly increased without serious structural alterations, for which there was simply no time. To obtain the required flight range of 2000 km, it was necessary to install tanks for 700 liters of fuel in the middle and tail parts of the fuselage - and, according to the conditions for balancing the aircraft, place these tanks not too far from the center of gravity. It turned out that in this case there is no room for a gunner-radio operator. One of the additional tanks was installed in the fuselage bomb bay, and the other two - in place of the gunner's cockpit. So the plane became a double. However, the lower hatch in the rear of the fuselage was left, and when relocated, the aircraft equipment flew away with their machines.
Armament. The fighter's offensive armament was somewhat strengthened by placing an additional 12.7 mm BK machine gun with 150 rounds of ammunition in the forward fuselage. Thus, the prototype aircraft's nose gun mount consisted of two BK heavy machine guns and one ShKAS with 750 rounds. On serial Pe-3s, the ShKAS machine gun was removed, but the ammo capacity of the BC was increased to 250 rounds per barrel.
The navigator's upper turret with the ShKAS machine gun was taken unchanged from the Pe-2. Since there was no one to fire back and forth, they remembered the tail fixed installation of the ShKAS machine gun with an ammunition load of 250 rounds, which was mounted in the fuselage tail spinner, still for the high-altitude fighter "100". The bomber installation was radically simplified. From the usual scheme for the Pe-2, only four bomb racks remained: two in the bomb bays of the engine nacelles and two external ones under the center section. The total weight of the bomb load was: normal - 400 kg, and reloading - 700 kg (two bombs of 250 kg and two more of 100 kg). The electrical bomb-dropping control system was dismantled, leaving only the emergency mechanical one. The brake grids under the consoles, along with the drives, were eliminated.
Pe-3bis. The pilots and navigators of the 95th Air Regiment, who had mastered the "pawn" quite well, easily adapted to the features of the fighter version. However, the shortcomings of the Pe-3 design noted above caused some of them bewilderment and even protest. The lack of armor in front meant that the crew was completely unprotected from the defensive fire of enemy aircraft. In the report of the regiment commander, Colonel S. Pestov, it was noted that if the armor was not installed, then "the regiment would not be enough for two attacks." The same point of view was defended by the squadron commander, Captain A. Zhatkov, who dared to take a desperate act: he sent a personal letter to the Secretary of the Central Committee of the All-Union Communist Party of Bolsheviks, Malenkov.
"As a commander of an aviation squadron, I want to fill you in on the poor quality of aircraft entering service with the Air Force," the letter began. Further, Zhatkov listed most of the shortcomings of the Pe-3, which were previously noted in the test report of the Air Force Research Institute. According to the pilot, in addition to the armor on the fighter, it was necessary to urgently install the ShVAK cannon and replace the upper installation of the navigator with the ShKAS with a turret with a BT heavy machine gun.
Zhatkov's letter served as a powerful stimulus for the accelerated modernization of the Pe-3 fighter, since Malenkov demanded that the Air Force command urgently investigate the situation and report to him. In addition, Petlyakov received a whole set of claims from the pilots of the 40th Sbap, which also began to re-equip the Pe-3. The shortcomings should be eliminated, and eliminated urgently. Work on the creation of a modified version became the main occupation for the entire Petlyakov Design Bureau in September 1941. As a result, an experimental improved Pe-3bis aircraft (the first with that name) appeared, tested at the Air Force Research Institute by pilot A. Khripkov in late September - early October. Aircraft No. 392207 during the tests made 40 flights.
The experimental Pe-3bis differed from the previously tested serial Pe-3 in the following features:
- instead of BK machine guns, two unified UBK heavy machine guns were installed in the forward fuselage, and the second machine gun was placed at the place where ShKAS was located near the Pe-2, i.e. directly in front of the pilot. Ammunition for UBK machine guns - 250 rounds per barrel;
- in the place where the lower heavy machine gun was previously located, a 20 mm ShVAK cannon with 250 rounds of ammunition was mounted;
- instead of the upper turret of the TSS-1 navigator with a ShKAS machine gun, a mobile turret with a UBT machine gun and an ammunition load of 180 rounds in a rotating turret was mounted;
- wing panels are equipped with automatic slats to increase the stability of the machine at low flight speeds;
- the cockpit canopy has been shortened, and the anti-bonnet frame has been moved forward by half a meter;
- the system for filling gas tanks with nitrogen was replaced by the so-called "neutral gas system" (cooled exhaust gases of engines were supplied to the tanks);
— curtains are installed on all cockpit windows to prevent dazzling of the crew.
The flight weight of the fighter increased to 8040 kg (180 kg more than that of the Pe-3), and the speed at the altitude limit slightly decreased - up to 530 km / h, but the speed near the ground increased to 448 km / h. Automatic slats somewhat simplified the piloting technique, especially on landing.
Despite repeated requests from the military, Plant No. 39 was unable to install the RPK-10 radio semi-compass on the Pe-3bis due to irregular deliveries. An unexpected consequence of the installation of the ShVAK gun in the forward fuselage was a large residual deviation of the A-4 magnetic compass, reaching two tens of degrees. These circumstances, combined with a decrease in the glazed area of the forward fuselage and the inevitable deterioration of orientation conditions, made it very difficult to fly over long distances, and indeed over unfamiliar terrain.
In addition to the above remarks and defects, this version of the Pe-3bis was also characterized by others inherited from the base bomber and mainly related to the power plant.
After the testing of the experimental Pe-3bis was completed, some changes began to be implemented on production aircraft. Individual machines (apparently, not all) were finalized in parts by mobile factory teams and specialists from the engineering and aviation service. The ShVAK cannon was installed on the aircraft, the ShKAS machine gun of the upper firing point was replaced with a large-caliber UBT (at the same time, the standard "turtle" - the rear movable part of the canopy was dismantled, but the rotating tower-screen was not yet used), a DAG-10 aircraft grenade holder was placed in the rear fuselage .
By the spring of 1942, the shortage of Pe-3s began to be acutely felt in the combat units of the Air Force and Navy aviation, because not a single new machine had been received since November. On March 4, the State Defense Committee adopted Decree No. 1385, according to which Plant No. 39 was obliged to restore serial production of twin-engine fighters from April 1942. Even a relatively small delay in the start of production caused an instant reaction: on April 6, Brigadier Seleznev, head of the Main Directorate for Orders and Technical Supply of the Air Force, personally turned to People's Commissar for the Aviation Industry A. Shakhurin with a request to “pull up” his subordinates: “Given the great need for twin-engine fighters, I ask you to oblige the plant No. 39 to speed up the production of Pe-3 aircraft ... "
The desire to improve the combat and operational qualities of the aircraft led to the creation of the second version of the Pe-3bis. The work was carried out in Irkutsk in late 1941 - early 1942. The Pe-3bis series was launched in April 1942 (in the same month, from the parts brought from Moscow, they managed to assemble another 11 "ordinary" Pe-3s, bringing them the total number is up to 207 units), and the experimental aircraft of the second variant (serial number 40143900) got to the Air Force Research Institute only at the end of May. Control tests were carried out by pilot M. Nyukhtikov. The differences between the machine and the first version of the Pe-3bis were as follows:
- UBK machine guns were removed from the forward fuselage and placed under the center section in place of the former Pe-2 bomb bay. Both UBKs were mounted on a common frame, closed with a light side-opening hatch. The front of the frame had trunnions, relative to which it could rotate when servicing machine guns. When the rear attachment points were released, the machine guns, together with the cartridge boxes, were lowered breech down, which greatly simplified the process of preparing weapons. The ammunition load of the right machine gun consisted of 230, and the left - of 265 rounds;
- instead of the turret developed for the first experimental Pe-3bis by plant No. 39, a serial installation designed by plant No. 32 (the so-called "Toropov's installation", aka VUB-1, aka B-270) was mounted on the navigator. The power supply of the UBK machine gun (on the turret was installed exactly wing, with electric trigger and pneumatic reloading, and not a special turret version of the Berezin machine gun) was belt, the ammunition consisted of 200 rounds. To increase the reliability of the installation, the machine gun was equipped with a belt electric pull-up device. During the tests, it turned out that the deflection of the machine gun to the sides by the efforts of the navigator at an angle of more than 40-50 ° at cruising flight speeds is impossible due to large aerodynamic loads. To eliminate this phenomenon, a two-leaf compensator was installed on the screen, which, however, turned out to be insufficiently effective;
- in the cockpit, as a necessary measure, the anti-bonnet frame was removed to improve the working conditions of the navigator in flight;
- the armor of the crew has been strengthened, while the total mass of steel armor has increased to 148 kg. The front of the pilot was covered with armor plates 4-6.5 mm thick, which could not be done on the first version of the Pe-3bis, the nose of which was literally “stuffed” with weapons. The armored back of the pilot's seat was made of steel 13 mm thick, and the windshields were made of 45 mm stalinite. In addition, the lower hatch of the cockpit was booked to protect against an accidental shot from the UBC at the time of boarding the aircraft;
- the glazing in the forward fuselage was eliminated, leaving only a small viewing hatch in front of the navigator for aiming when bombing from level flight;
- the transfer of weapons to the center section required a decrease in the capacity of gas tank No. 7 and a fuel reserve of 100 liters. To isolate the tank and protect it from heating, an asbestos partition was introduced, which at the same time served as a screen that protected machine guns from gasoline leaking onto them;
- the area of the keels was increased by 15% to improve directional stability (only on an experimental aircraft);
- installed an anti-icing system on the propellers and windshield of the cockpit lantern;
- instead of regulators of constant revolutions of the R-3 propeller with electric remote control, the disadvantage of which was the possibility of spinning the propellers when exiting a dive, they mounted the R-7 units with helm control from the cockpit.
The center of gravity of the aircraft, especially when landing with empty tanks, shifted noticeably forward due to the placement of the cannon and armor in the forward fuselage. All this led to a decrease in the anti-cocking angle and the impossibility of effective braking - the aircraft strove to “stand on its nose”. In order to eliminate the drawback, the struts of the main struts were lengthened, as a result of which the wheels in the released position shifted forward by 60 mm. This turned out to be enough for some improvement in the behavior of the fighter on landing.
The normal flight weight of the Pe-3bis was 8002 kg. The maximum flight speed compared to the machine of the first variant slightly decreased: near the ground to 438 km/h, and at altitude - up to 527 km/h (due to the turret compensator, increased keels and ventral machine guns). For a combat turn, the aircraft gained 540 m, the turn time at an altitude of 1000 m was 30 s, and the fighter gained a height of 5000 m in 9.65 minutes. These flight data can be considered typical for the serial Pe-3bis produced in 1942. The serial numbers of serial machines were six-digit, for example, 400105, which meant Pe-3bis (40), the fifth aircraft (05) of the first series (01). In some documents, the second "zero" in the serial number was not indicated, since the number of Pe-3bis series did not exceed a dozen.
In July 1942, Plant No. 39 overfulfilled the program set by the government.
In 1942, Plant No. 39 produced 121 Pe-3bis. Another 13 machines in the long-range reconnaissance version were completed and handed over to combat units at the beginning of 1943. At this point, production of the Pe-3bis was discontinued (the M-105R engines needed for these aircraft were searched for a long time throughout the country, since the Pe-2 dive bombers by that time, they began to mount less high-altitude, but somewhat more powerful M-105PF). Since the autumn of 1942, the enterprise switched to the mass production of long-range bombers Il-4.
The first serial Pe-3bis (20 units) in June 1942 entered service with the 9th bbap. Then came the turn of the 2nd, 4th and 40th separate distant reconnaissance regiments. Several aircraft were received by the 9th reconnaissance squadron, and later by the 1st and 39th air regiments of the KA Air Force. In response from the front, many pilots considered the Pe-3bis more valuable and useful than the standard Pe-2. In naval aviation, the largest number of Pe-3bis (no more than a dozen) was transferred to the 65th Aviation Regiment.
In total, about 360 serial Pe-3 aircraft were produced.
'' On the external suspension
''' On the external suspension and in engine nacelles compartments
'''' In engine nacelles compartments
At the end of August 1941, Moscow Plant No. 22, on its own initiative, proposed its own version of the conversion of the Pe-2 into a fighter. Pe-2I (the first with such a name), head. number 5/33 according to the numbering adopted at this plant (i.e. the fifth aircraft of the thirty-third series), unlike the Pe-3, had much more powerful weapons. In place of the bomb bay, a two-gun ShVAK installation with 160 rounds of ammunition per barrel was mounted on it. Armament in the forward fuselage remained unchanged from the Pe-2.
The Pe-2I, like the Pe-3, became a two-seater. A 240-liter gas tank was installed in the cockpit of the gunner-radio operator, and the volume of center-section tanks was increased by 70 liters. And yet, the fuel was not enough to ensure a flight range of 2000 km. Therefore, they used (for the first time on the Pe-2) a suspension on the center-section bomb racks of two additional tanks with a capacity of 180 liters each, which could be dropped after running out of fuel.
Other modifications of the machine (removal of the brake flaps, "fighter" radio station, etc.) were identical to the Pe-3. However, instead of the ShKAS in the tail fairing, a non-movable BT machine gun was mounted under the fuselage on the Pe-2I. Oriented backwards with an inclination of approximately -5 °, the machine gun was located under the place where the gunner's cabin had previously been. In the conclusions of the Aircraft Testing Act, instead of a fixed one, it was recommended to develop a remote-controlled installation of a BT machine gun.
A major drawback of the Pe-2I aircraft was the lack of armor protection for the crew in the front, which is very necessary when attacking a defending enemy, although it was generally not difficult to install it, at least not more difficult than on the Pe-3. In terms of design and production performance, the Pe-2I turned out to be more advanced and, on the whole, had certain advantages over the "competitor" of the 39th plant, especially in relation to weapons. In addition, according to the plant, the Pe-2I at all altitudes was about 10 km / h faster than the Pe-3, and it gained a height of 5000 m 30 seconds faster. However, KB-39 disputed the figures given by plant No. 22, indicating that they were obtained by applying a "little trick". It turns out that in test flights for speed, ceiling and rate of climb, the Pe-2I flew without underwing tanks (i.e. with reduced weight and better aerodynamics), and for maximum range with them, while the Pe-3 was tested with a constant takeoff mass and configuration.
In order to work out the tactics of twin-engine fighters during the tests of the Pe-2I, they conducted a series of training air battles with the SB bomber and the MiG-3 fighter. The duel with the SB convincingly testified that the Pe-2I freely overtakes him and attacks from any direction, but has worse maneuverability in the horizontal plane, so the fight on turns is contraindicated for him. When meeting with a MiG-3 class fighter, Petlyakov found himself in a difficult position. In this case, two tactics were recommended to his crew: attacking on a collision course or avoiding the enemy with a slight decrease at full throttle.
The Pe-2I aircraft was not put into mass production (the plant was fully occupied with the production of the Pe-2). Later, some of the ideas that arose during its development were used in the design of the latest version of the Pe-3, which was built in a small series at factory No. 22 in 1944.
Heavy Night Fighter
According to the estimates of the Research Institute of the Radio Industry, made in 1940, an aircraft radar created on the basis of the technology of that period of time, together with power supplies and cables, should have weighed at least 500 kg. Placing such massive equipment on a single-seat fighter seemed clearly impossible. In addition, the operation of the station required continuous maintenance (with the then level of radio engineering, automation was out of the question), which would distract the pilot from piloting.
The way out suggested itself - the installation of an airborne radar could only be implemented on a multi-seat aircraft. At the suggestion of the test pilot of the Air Force Research Institute S.P. Suprun decided to use the Pe-2 aircraft as a carrier.
At the beginning of 1941, a functioning model of the station, called "Gneiss-1", was built at the Research Institute of the Radio Industry. The first airborne radar, of course, turned out to be very imperfect. In addition, during the experiments, the entire supply of centimeter-range generator klystron lamps, the “heart” of the future radar, was used up, and there was no place to order new ones. The war began, many enterprises of the electrical and radio industries had to be evacuated to the East, and among them was the NII-9 that developed the lamps. Its equipment and specialists were scattered around different factories, and NII-9 itself actually ceased to exist. They were evacuated to Sverdlovsk and the Research Institute of the Radio Industry. At the new location, the laboratory and testing facilities had to be rebuilt.
A new set of equipment was developed on meter-range lamps mastered in mass production. The creation of this version of the station, called "Gneiss-2", was headed by V.V. Tikhomirov. A target indication device based on a cathode ray tube, which made it possible to visually determine the distance to the target and its position in space, was developed by A.B. Slepushkin and R.S. Budanov. From the Air Force Research Institute, the work was supervised by military engineer E.S. Matte
To speed up the work, the manufacture of equipment was carried out without waiting for the complete release of the documentation. Installation was carried out according to sketches and a schematic diagram, making changes on the go and getting rid of defects. By the end of 1941, the first “flying” model of the Gneiss-2 radar with a radiation power of 10 kW, operating at a wavelength of 1.5 m, was assembled.
In January 1942, at the airfield near Sverdlovsk, where the Air Force Research Institute was relocated, the station was mounted on a Pe-2 aircraft. Soon the tests began. Note that the controls and the Gneiss indicator were placed in the radar operator's cab (where the navigator used to sit), and some of the station's blocks were mounted in the gunner-radio operator's cab. The aircraft became a two-seater, which had a negative impact on its combat capabilities. In parallel with the assessment of the performance of the radar, which was, in fact, an experimental model, the methods and tactics of the combat use of a radar fighter were worked out. The Pe-2 was piloted by Major A.N. Dobroslavsky. Leading engineers V.V. themselves worked with Gneiss. Tikhomirov and E.S. Matte. The SB aircraft was used as the target.
In the very first flights, it turned out that the station has a large "dead zone" near the aircraft, in which the signals reflected from the target are suppressed by the transmitter's own interference. Another feature of the station was also discovered: to increase the field of view, its antenna device had a very wide radiation pattern. In this regard, when flying at low altitudes, the overview screen was completely “clogged” with signals reflected from the ground. If the plane was gaining altitude, then its station was unable to detect targets flying lower and invisible against the background of the earth. The minimum height at which the problems associated with reflection from the ground disappeared was about 2000 m.
Fine-tuning of the equipment was carried out around the clock, right there at the airfield. Failures were eliminated, various types of antennas were tested, changes were made to the design of the radar, which made it possible to reduce the "dead zone" to 300 m (and then to 100 m) and improve the reliability of the station. In July 1942, the state testing program was completed. The main results were, at that time, not bad:
bomber detection range 3500 m;
accuracy of reaching the target 5°;
the minimum flight altitude when searching for an enemy is 2000 m.
The test results were considered successful, although the radar station needed to be improved: out of 25 flights performed, the Gneiss-2 equipment failed in 5 cases. Air defense aviation needed new equipment (and in 1943 the Air Force of the Navy was among the customers), and even before the end of the tests, the institute began manufacturing 15 pre-production sets of the station, with which the Pe-2 and Pe-3 aircraft were equipped. At the end of 1942, the planes were handed over to Moscow's air defense, and then several planes were transferred to Stalingrad to fight the German transport workers supplying Paulus' encircled army.
Official military tests of the Pe-2 with the Gneiss-2 were carried out in February-May 1943 near Leningrad in the 2nd Guards Air Defense Corps. When intercepting air targets, the fighters were guided by ground-based early warning radars "Redut". The chairman of the testing commission was the corps commander Hero of the Soviet Union, Major General E.E. Erlykin, V.V. participated in the work from the developer. Tikhomirov and from the Air Force Research Institute - engineer E.S. Matte.
At the same time, tests of the Gneiss-2 on the Pe-3 fighter at the Air Force Research Institute continued, the task of which was to develop rational tactics for intercepting air targets. Targeting the enemy aircraft was carried out in two stages: at the first stage, according to the commands of the Pegmatit ground-based radar operator with a range of 100 km, and at the final stage, using the onboard station. The joint operation of the two devices was excluded due to the interference created by the Gneiss transmitter. The Pegmatite operator was required to bring the “pawn” into the rear hemisphere of the enemy aircraft at a distance of no more than 3000-3500 m. . Naturally, ensuring such an accurate approach to the target, taking into account the imperfections of the then equipment, was not an easy task, it required high coordination and mutual understanding between the ground-based RAS operator and the fighter pilot. Not without reason in the conclusions on the tests they wrote: "The level of training of guidance operators is of decisive importance ..."
On June 16, 1943, by a decree of the GKO, the Gneiss-2 station was put into service, and the Research Institute of the Radio Industry was instructed to manufacture a large batch of radars. For this purpose, the institute with all the backlog of equipment was returned from evacuation, and on the basis of the Air Force Research Institute, a team of specialists led by V.V. Tikhomirov began assembling and setting up stations.
Note that at about the same time V.V. Migulin and P.N. Kuksenko, another aircraft radar of the PNB type (night combat device) was also created. It had characteristics similar to Gneiss-2, however, it was inferior to it in terms of manufacturability and was not transferred to serial production.