Following the acquisition of the first captured German turbojets at the end of 1944, various Soviet design bureaux were ordered to begin a crash programme aimed at producing operational fighters designed around these engines. The bureaux involved were Mikoyan and Guryevich (MiG), Lavochkin, Sukhoi and Yakovlev. By the time initial design studies were nearing completion, copies of the German engines were already in production, the BMW 003 as the RD-20 and the Jumo 004 as the RD-10.
Each design bureau tackled the problem in its individual fashion, all from a starting point in February 1945. While Mikoyan and Guryevich set about designing a fighter around a pair of BMW 003A engines, Sukhoi adopted a design with twin underslung engines reminiscent of the Messerschmitt Me 262; Lavochkin came up with an aircraft built around a Jumo 004 engine mounted in a fuselage pod; while Yakovlev opted for an adaptation of their existing and well-proven Yak-3 fighter. The resulting aircraft, designated Yak-15, flew for the first time on 24 April 1946. Deliveries to Soviet Air Force fighter squadrons began early in 1947. Production aircraft retained a tailwheel undercarriage and were powered by the RD-10 engine. About 280 were built. At the time of its introduction the Yak-15 was the lightest jet fighter in the world, the lightweight structure of the Yak-3’s airframe compensating for the relatively low power of the engine. The Yak-15’s NATO reporting name was ‘Feather’.
The MiG design was the I-300, the I standing for Istrebitel, or interceptor. Although the aircraft was powered by two engines, mounted side-by-side in the centre fuselage, it was by no means heavy, the loaded weight being in the region of 11,000 lb. The I-300 featured the first tricycle undercarriage installed on a Russian-built aircraft, the narrow-track mainwheels retracting outwards into the wings. Three I-300 prototypes were built, the first of which had its maiden flight on 24 April 1946 with test pilot Alexander Grinchik at the controls. During subsequent testing, the maximum speed was gradually pushed up to 566mph. Severe vibration was experienced in the higher speed range, and it took a considerable time before the cause was established. The jet efflux, exhausting under the tail, was buffeting the fireproof sheathing of the rear fuselage undersurface and setting up resonance throughout the airframe.
A month after the aircraft’s first flight, while Grinchik was carrying out a high-speed, low-level run in the first prototype the aircraft suddenly developed an uncontrollable pitch and dived into the ground, killing its pilot. Grinchik’s place was taken by Mark Gallai who, together with Georgii Shianov, continued the flight test programme with the two other aircraft. Gallai enjoyed enormous prestige with the elite Soviet test pilot fraternity. He came from a Jewish family, which might have been a problem for career advancement under the Soviet system, but his manifest skills as a pilot and engaging personality won him respect everywhere. His flight log included some of the most important aircraft of the period after the Second World War. Gallai flew more than 200 types of aircraft, even taking the controls of the Luftwaffe’s dangerous Me 163 interceptor.
Both pilots experienced a high workload, as the I-300 was difficult and often unpleasant to fly, many of its problems resulting from the haste with which it had been completed. On one occasion, Gallai almost came to grief when, during a high-speed run at Mach 0.8, the nose of the aircraft pitched down violently. He reduced power and managed to restore full control, but after landing it was found that both the tailplane and elevator had become distorted. In all probability, Gallai had experienced the problem that had killed Grinchik.
On another occasion, Gallai was carrying out a high-speed run at 2000 feet when the I-300 virtually went out of control; fortunately, the nose went up instead of down and the aircraft gained several thousand feet of altitude, vibrating badly, with the pilot practically helpless. Gallai reduced power and restored partial control, looking back to check the tail; to his dismay he saw the port tailplane was no longer there, and the starboard tailplane was badly distorted. To make matters worse, fuel from a ruptured tank was seeping into the cockpit and there was a severe fire risk. Gallai would have been quite justified in baling out, but he was a test pilot of the highest calibre. Cutting both engines, he managed to bring the aircraft back for a dead-stick landing.
Despite its vicissitudes, the I-300 was ordered into production for the Soviet Air Force as the MiG-9 and, with a redesigned nose to accommodate one 37 mm and two 23 mm cannon, was the first Russian jet type to reach squadron service, the first deliveries being made in December 1946. Although technically far from reliable, it provided Russian fighter pilots with valuable experience in jet operation.
While striving to bring the MiG-9 to production standard, Mikoyan was also studying other fighter projects. In 1946, the MiG bureau built and tested a rocket-powered target defence interceptor, the I-270 (Zh), which was based on the wartime Messerschmitt Me 263A rocket fighter project.
The first Russian attempt to produce a short-range, rocket-propelled target defence interceptor, designed to have a rate of climb of 35,400 ft/min, had been made some years earlier. This was the Bereznyak-Isayev BI-1. It was to be powered by a Dushkin D1 rocket motor, which was successfully tested in a glider that had been towed to altitude. Of mixed construction, the BI-1, a small low-wing monoplane, was built in only forty days, and was flown as a glider for the first time on 10 September 1941. The first powered test flight was made on 15 May 1942 and was successful, but shortly afterwards the prototype was destroyed when it crashed during a maximum-power run at low level. Despite this setback seven pre-series aircraft were built and the programme went ahead. However, subsequent flight trials revealed unforeseen aerodynamic problems. Also, Dushkin’s work on a multi-chamber rocket motor encountered innumerable snags, and the powered endurance of eight minutes was considered insufficient for operational purposes. All these problems brought an end to the project.
Whereas the Me 263A had been a swept-wing design, the I-270 employed an unswept wing of thin section and slightly swept horizontal tail surfaces, mounted T-fashion on top of the vertical surfaces. The Russian aircraft was powered by an RD-2M-3V bi-fuel rocket motor, which was a slightly modified version of the Walter HWK 509C; it was equipped with main and cruising chambers, the former giving a maximum endurance of 4 minutes 15 seconds and the latter 9 minutes 3 seconds. The first airframe, Zh-1, began glider tests in December 1946, towed by a Tupolev Tu-2 to its release point. The Zh-2, rocket-powered with a dual thrust engine (1650 kg boost / 400 kg cruise), first flew in March 1947. However, the total burn time of the rocket engines was only 255 seconds, and by this time the prototype of the faster and much longer-ranged turbojet-powered MiG-15 was nearing completion. Therefore, the I-270 was seen as having no military utility and abandoned after the Zh-2 was written off in a hard landing in the spring of 1947. Under test, the I-270 reached an altitude of 32,810 feet in 2.37 minutes, and 49,215 feet in 3.03 minutes. The maximum speed was 620 mph, and the proposed armament was two 23mm cannon.
In the late 1940s Yakovlev built the prototypes of three single-seat fighter designs, none of which came to fruition. The first, in 1947, was the Yak-19, a simple and uncomplicated aircraft with unswept flying surfaces and powered by an RD-500 (based on the Rolls-Royce Derwent) turbojet. The Yak-19, in fact, served as the prototype of a more refined design, the Yak-25; this had a similar powerplant, but was fitted with swept tail surfaces and wing-tip drop tanks. The Yak-25 was intended to fulfil the same tactical role as the Republic F-84 Thunderjet, but it had extremely disappointing performance figures and was consequently abandoned. Its designation was allocated to a later – and vastly more successful – fighter type, the Yak-25 ‘Flashlight’.
The other Yakovlev jet fighter design of the 1940s was the Yak-30, a swept-wing fighter built to the same specification as the MiG-15. Powered by an RD-45 (Rolls-Royce Nene) turbojet, the Yak 30 first flew in 1948; the maximum speed was 640 mph, the service ceiling was 49,500 feet and the range was 900 miles. The Yak-30 underwent comparative trials with the MiG-15, from which the Mikoyan fighter emerged as the better aircraft on all counts.
In the original race to produce a jet fighter in 1945–6, Mikoyan had been ordered to design an aircraft around two Junkers Jumo 004A turbojets; the result, as we have seen, was the MiG-9, the first jet fighter to enter Russian service. Another designer with the same brief was Pavel Sukhoi, whose Su-2 ground attack aircraft had filled a dangerous gap during the war until the deployment of the Ilyushin Il-2. However, his subsequent designs, although often advanced and sometimes aerodynamically better than some that achieved production status, had laboured under a series of misfortunes – often caused by the lack of suitable engines. Consequently, they had never met with the success they deserved. Nevertheless, Sukhoi was one of Russia’s most experienced aeronautical engineers, and it was logical that his expertise should be put to good use in the jet fighter development programme.
Sukhoi approached the design of his first jet fighter, the Su-9, with a good deal of caution, preferring to adopt a similar configuration to that of the Messerschmitt Me 262 – although the aircraft that emerged was by no means a copy of the German fighter. The Su9’s engines were placed in underwing nacelles and the aircraft had an Me 262-style cockpit, but there the resemblance ended. The flying surfaces were less angular and the wings were unswept, while the fuselage was deeper and slimmer than the Me 262’s. The only aspect, apart from the engines, that might be said to have been copied from the Me 262 was the tricycle undercarriage. Even here, there were distinct differences.
Like the MiG-9, the Su-9 was armed with one 37 mm and two 23 mm cannon, and for short take-off a pair of solid-fuel rockets could be attached under the fuselage. The Su-9 was generally a more refined design than the MiG aircraft; among other items, it featured a compressed-air ejection seat, modelled on German equipment, and a braking parachute. The aircraft flew for the first time in 1946, some months after the MiG-9, and the performance figures for the two aircraft were not dissimilar. Although the Su-9 was slightly inferior to the MiG-9 at high altitude, its range performance adequately compensated for this, and it also carried more ammunition. In view of the MiG-9’s appalling safety record, there seemed no reason why the Sukhoi aircraft should not have been selected in preference.
But there was a reason, and it was an extraordinary one. It appears that other Soviet designers, eager to have their own aircraft accepted, ‘ganged up’ on Sukhoi at a conference in 1946. They persuaded Josef Stalin that any machine that resembled the Messerschmitt Me 262 would be unacceptable because the German fighter had proved dangerous to fly. Stalin was by no means an aviation expert, but he had seen photographs of the Me 262, and to his mind the Su-9 was sufficiently like it to be seen in an unfavourable light. In all probability, Stalin’s concern was not so much to do with safety concerns, but more to do with a desire to show the world that the Soviet regime was capable of producing modern aircraft without being accused of copying those of its former enemy. So, after one brief appearance at the Tushino air display on 3 August 1947, the Su-9 was abandoned and the Soviet Air Force took delivery of the heavy, unwieldy MiG-9, which killed its pilots in considerable numbers.
Following this disappointment, Sukhoi now pinned his hopes on the development of two advanced jet fighter projects, the Su-15 and Su-17. By 1948, the Russians – again relying heavily on German technology – had developed an AI (airborne intercept) radar known as Izumrud (Emerald), which was intended to equip a new generation of all-weather fighter aircraft. Sukhoi’s response to the specification was the Su-15, which was also known as the Samolyot P. Powered by two RD-45 turbojets, the aircraft had a mid-mounted wing with a leading edge sweep of 37 degrees. The twin engines were mounted one above the other in a deep centre fuselage and exhausted below the fuselage aft of the trailing edge. The AI scanner was housed in a small radome situated above the nose air intake, and the armament comprised two 37 mm cannon mounted one on either side of the nose. With a loaded weight of 23,000 lb, the Su15 was a very heavy aircraft; nevertheless, its designers estimated that it would have a maximum speed of 641 mph, a service ceiling of 45,930 feet, and the ability to reach 32,800 feet in six and a half minutes. These figures were never proved, because the Su-15 disintegrated following severe vibration on an early high-speed run (the pilot ejecting), and no further prototypes were built.
Work continued in 1949 on the Su-17 supersonic fighter project, which was to have been powered by a Mikulin TR-3 axial-flow turbojet and had wings swept at 50 degrees. The estimated performance figures included speeds of Mach 1.08 at 36,090 feet and Mach 1.02 at sea level, with a service ceiling of 50,850 feet. A novel feature of the Su-17 was that in an emergency the fuselage nose, including the cockpit, was intended to be blasted clear of the rest of the airframe by explosive charges and stabilised by a drogue. The pilot would subsequently eject in normal fashion. By this time, however, Sukhoi had fallen out of favour with the Ministry for Aeronautical Development and Production. In 1949, on orders from Moscow, his factory was closed down. All work on the Su-17, the airframe of which was partially complete, was brought to a halt and the aircraft broken up for scrap. Despite these misfortunes, Pavel Sukhoi was later to bounce back into the limelight of Soviet fighter design.
The first venture into the jet fighter field by the other leading Soviet designer, Semyon A. Lavochkin, was the La-150, which was powered by a single RD-10 (Jumo 004A) turbojet. The aircraft, which was flown for the first time in September 1946 by test pilot A.A. Popov, featured a ‘pod and boom’ design, with unswept shoulder-mounted wings and a tricycle undercarriage mounted in the lower fuselage. The armament comprised two 23 mm NS cannon, one on either side of the nose. Two prototypes were built, and these reached a maximum speed of 500 mph at 16,400 feet; the service ceiling was 41,000 feet. Three more aircraft were completed and fitted with uprated RD-10F engines, being redesignated La-150M. However, the flight characteristics of the Lavochkin design left much to be desired – severe oscillation of the tail boom was only one of its problems – and further development was abandoned in April 1947.
Meanwhile, Lavochkin had also begun work on three more fighter prototypes, the La-152, La-154 and La-156, all of which featured a configuration that was closer in style to that of Yakovlev’s Yak-15. The fuselage undercarriage arrangement was retained, but the wing was mounted at mid-point and the cockpit was positioned well aft, over the trailing edge. However, although the handling characteristics of these three aircraft were somewhat better than those of the La-150, performance was actually poorer, and they were used only for experimental flying.
By the middle of 1947, Russian designers were overcoming an early aversion to the use of sweepback (an aversion that was shared by their British and French counterparts), and Lavochkin decided to fit the basic La-152 fuselage with swept flying surfaces. The result was the La-160, which had a wing swept at the optimum 35 degrees and an armament of two NS-37 cannon. The aircraft flew for the first time in 1947 and was claimed to be the first postwar swept-wing jet fighter, but in fact it was used purely for aerodynamic research and never went into production.
The last of Lavochkin’s straight-wing designs was the La-174TK, the ‘TK’ denoting Tonkii Krylo, or thin wing. Apart from the wing design, the main difference between this aircraft and the La-152, La-154 and La-156 was that it was powered by an RD-500 (Rolls-Royce Derwent) engine and carried an armament of three NS-23 cannon. The La-174TK, which first flew early in 1948, was in fact something of an anachronism. It contributed nothing to Soviet aeronautical knowledge, except to underline the fact that the straight, thin wing offered no advantages over the swept planform. Before the La-174TK even flew, Lavochkin was already studying two infinitely more advanced jet fighter designs, produced to the same specification as the successful MiG-15. The first of these was the La-168, which was intended to be powered by an RD-10 turbojet. However, when the Lavochkin team discovered that the MiG design, which weighed about the same as their own, was to be fitted with a much more powerful Rolls-Royce Nene engine derivative, they realised that the La-168’s chances of success were very slender indeed by comparison. Lavochkin therefore set about building a second prototype, similar in configuration to the La-168 but powered by the production version of the RD-500 Derwent. Somewhat confusingly, this aircraft was given the designation La-174
The prototype of Lavochkin’s La-174 flew first shortly after the La-168 and went on to enter Soviet Air Force service in 1949 as the La-15. However, its performance proved inadequate for the interceptor role. Only a few ground-attack units were equipped with it, the MiG-15 becoming the standard Soviet interceptor of the late 1940s. About 500 La-15s were built.
The first-generation Soviet jet fighters of the 1940s were notable for their ugliness, excessive all-up weight and poor aerodynamic qualities. Nowhere were these shortcomings more apparent than in early Russian attempts to produce a viable all-weather fighter. In 1950, one of the Soviet Air Force’s main preoccupations was to bring a true all-weather fighter into service. A specification written around this requirement had been issued two years earlier, and the leading Soviet design bureaux had responded to it; Sukhoi, as we have already seen, produced the Su-15, which broke up in mid-air. The main problem encountered by the designers was that existing power plants were inadequate to compensate for the weight increase that went with the installation of bulky AI radar equipment and the requirement that the proposed fighter had to be a twin-engined machine.
The main contenders in the race to produce a Russian night fighter were Mikoyan, Lavochkin and Yakovlev. Mikoyan’s design, the single-seat I-320(R), was powered by two Klimov VK-1 turbojets and first flew in 1949; it was based on the MiG-15, but the engine installation resulted in a bulky, ungainly aircraft with poor handling characteristics and even worse visibility for the pilot, whose forward view was badly obscured by the long nose and radome.
Lavochkin’s design, the La-200A, was a better proposition from several points of view, but suffered from the same engine arrangement as the I-320(R). In both cases, the VK-1 engines were fed via a common nose air intake, but in the La-200A they were installed in tandem, the first exhausting under the fuselage and the second under the tail. This necessitated some complex ducting that resulted in an inordinately large fuselage. A central air intake cone housed the La-200A’s Izumrud radar and the fighter was a two-seater, the pilot and radar observer seated side by side. The La-200A had a fuselage-mounted undercarriage and carried an armament of three 37 mm cannon, which contributed to the high all-up weight of 22,873 lb. Like the I-320(R), the La-200A first flew in 1949, and during trials reached a maximum speed of 660 mph at 16,400 feet; the service ceiling was 59,700 feet.
Neither aircraft underwent extensive operational trials, because in 1950 a developed, lighter version of the Izumrud AI radar was successfully installed in a two-seat MiG-15 variant known as the SP-5; both MiG-15s and MiG-17s were subsequently equipped with AI. These variants, however, did not meet the urgent requirement for an all-weather fighter fitted with long-range AI radar, and a specification for such an aircraft was issued in November 1951.
Lavochkin set about modifying the La-200A to carry a new radar scanner in a lengthened fuselage nose. The result was the La-200B, one of the ugliest fighter aircraft ever flown. The massive radome ruled out a single air intake, so the engines were fed by three ducts, one on either side of the nose and one underneath it. Bulky auxiliary fuel tanks were fitted under the wings, and to compensate for the extra weight – the aircraft now weighed 24,750 lb loaded – the undercarriage was strengthened. The La-200B was not the solution to the Soviet Air Force’s night fighter deficiency, which was not made good until the deployment of the Yakovlev Yak-25 ‘Flashlight’ in 1955.
Meanwhile, Russian aeronautical scientists had been exploring the realms of high-speed, high-altitude flight with the aid of the DFS 346, a German rocket-powered research vehicle built from technical files captured at the end of the the Second World War. At Podberezhye, the Russians set up a research bureau called OKB-2, directed by a German engineer, Hans Rossing, and A. Y. Bereznyak, the man responsible for the BI-1 target defence interceptor of the Second World War. Most of the personnel were German, former employees of the Siebel company, which was to have built the aircraft at Halle, in Germany.
By the time a second group of German engineers arrived at Podberezhye in October 1946, several models of the DFS 346 were under test, and the full-size aircraft was completed in 1947. The aircraft, which was unpowered, was designated 346P and was designed to perfect landing techniques, gliding in to land after being dropped by its parent aircraft. In all other respects it resembled the intended powered version. The fuselage had an unbroken cigar-shaped profile with mid-mounted wings swept back at 45 degrees and a short, broad fin and rudder unit supporting a swept-back, high-mounted tailplane. The pilot lay in a prone position behind a glazed nose cone.
In 1948 the 346P was transferred to the flight test airfield at Toplistan, near Moscow, where several unpowered, towed flights were made by two German test pilots, Rauschen and Motsch. Powered flights were to be made by another German, Wolfgang Ziese, who had been Siebel’s chief test pilot. The powered version of the 346 (it is unclear whether this was a new aircraft, or the original one equipped with a rocket motor) was completed in 1949, the aircraft being designated 346D.
On 30 September 1949, the 346D, with Ziese at the controls, was positioned under the starboard wing of its mother ship, a Boeing B-29 called Ramp Tramp (one of three that had made emergency landings in Russia after attacking Japanese targets in Manchuria in 1944). Ziese lit the rocket motor (a Walter HWK-109-509C) a few seconds after the drop and almost imediately experienced control difficulties. Recovering to Toplistan, he touched down at nearly 200 mph on the 346D’s landing skid, causing damage to the aircraft and injuring himself.
After the aircraft was repaired, testing resumed at Lukhovitsy airfield in October 1950, the pilot being a Russian, P.I. Kasmin. On 10 May 1951, Wolfgang Ziese, now recovered from his injuries, successfully flew the 346D under power, and on 16 June he made a gliding flight in a second aircraft, designated 346-3. On 13 August 1951 Ziese made a powered flight in the 346-3, somewhat disappointed by the knowledge that in the light of wind tunnel tests the aircraft would never fly supersonically and that it was limited to Mach 0.9.
Ziese made another successful flight on 2 September 1951, but during a third flight on the 14th the aircraft went out of control at 22,000 feet. Ziese had no alternative but to use the 346’s novel escape system. The whole nose section was jettisoned by firing explosive attachment bolts and he was pulled clear by the automatic deployment of a parachute.
It was the end of the 346 test programme. In 1953 the German scientists and engineers were repatriated to East Germany. Where, they first heard the news, denied to them during their enforced stay in Russia, that an American research aircraft, the Bell X-1, had flown faster than the speed of sound six years earlier.