Category Soviet x-plenes

Purpose: To create a Vintokryl (screw wing) compound helicopter.

Design Bureau: OKB ofNikolai Kamov, Moscow.

In 1951 various attempts were being made to increase the effective range of helicopters, notably by towing them in the outward direc­tion behind an Li-2, with the lifting rotor au- torotating. The idea occurred to Kamov designer Vladimir Barshevsky that it would be possible to dispense with the tug aircraft if a helicopter could be provided with wings and an aeroplane propulsive system. After obtain­ing permission from Kamov, his deputy V V Nikitin took a proposal to the Kremlin and in a matter of days the OKB had a Stalin di­rective to get started. The engines were to be TV-2 (later TV-2VK) turboshafts supplied by N D Kuznetsov, and many organizations were involved in research for this challenging pro­
ject, starting with model tests in the T-l 01 tun­nel at CAHI. The final go-ahead was issued on 11 th June 1954. An order for three Ka-22s was placed on the factory at Ukhtomskaya, which had been derelict since Kamov was evacuat­ed from there in October 1941. Concentration on the small Ka-15 (the OKB’ sfirstproduction helicopter) and other problems so delayed the programme that on 28th March 1956 pro­totypes 2 and 3 were cancelled. In June 1958 the LD-24 rotor blades began testing on an Mi-4. The Ka-22 itself first lifted from the ground on 17th June 1959, and made its first untethered flight on 15th August 1959, the test crew being led by pilot D K Yefremov. Serious control difficulties were encoun­tered, and the Kamov team were joined by LII pilots VVVinitskii and YuAGarnayev. Though still full of problems the Vintokryl was demonstrated on llth October 1959 to MAP Minister PVDement’yev and WS C-in-C

KAVershinin. Gradually difficulties were solved and in July 1960 an order was received to manufacture three Ka-22s at GAZ No 84 at Tashkent, with D-25VK engines. On 23rd May 1961 a speed of230km/h was held for 37 min­utes. On 9th July 1961 the Ka-22 caused a sen­sation at the Aviation Day at Tushino. On 7 th October 1961, with spats over the wheels and a fairing behind the cockpit, a class speed record was set at 356.3km/h (221.4mph), followed on 12th October by 336.76km/h (209.3mph) round a 100km circuit. The spats and fairing were then removed and on 24th November 1961 a payload of 16,485kg (36,343 Ib) was lifted to 2,557m (8,389ft). Preparations were then made to ferry AM 0I – 01 and the third machine AM 0I-03 from Tashkent to Moscow for Nil acceptance test­ing. Both departed on 28th August 1962. While making an intermediate stop at Dzhusaly 0I-01 rolled to the left and crashed inverted, killing Y efremov and his crew of six. The cause was diagnosed as ‘disconnection of No 24 cable joint of the linkage with the starboard lift rotor collective-pitch control unit’. At Tashkent and in Turkestan the cable joints and cyclic-pitch booster brackets were inspected on 0I-02 and 0I-03 and found to be incorrectly assembled. Changing the direc­tion of rotation of one lifting rotor did little at lower speeds and caused problems at higher speeds – ‘When’, said lead engineer V S Dor – dan, ‘Shockwaves off the blades sounded like a large machine gun’. To improve stability and controllability the complex AP-116 differ­ential autopilot was installed, continuously sensing attitude and angular accelerations, feeding the KAU-60A combined flight-control unit. On 12th August 1964 the heavily instru­mented 0I-03 took off on one of a series of tests conducted with WS (air force) and GVF (civil) crews. Take-off was in aeroplane mode, and 15 minutes later at 310km/h (193mph) the aircraft suddenly turned to the right, ‘not arrested by full rudder and aileron.. .the aircraft turned almost 180° when Garnayev intervened, considering the prob­lem was differential pitch of the pro – pellers…turn rate slowed, but the aircraft pitched into a steep dive…the engineer jetti­soned the flight-deck hatches, and one struck the starboard lift rotor causing asymmetric forces which resulted in separation of the en­tire starboard nacelle. Garnayev ordered the crew to abandon the aircraft’. Three survived, but Col S G Brovtsev, who was flying, and technician A F Rogov, were killed. By this time the Mi-6 heavy helicopter was in wide service, and the Ka-22 was ultimately aban­doned. Several years later the two surviving machines, 0I-02 and 0I-04, were scrapped.

An article about the Ka-22 in Kryl’ya Rodiny (Wings of the Motherland) for November 1992 does not mention the fact that two crashed, which is not widely known even in the former Soviet Union.

The Ka-22 was basically an aeroplane with its engines on the wingtips, with geared dri­ves to both propellers and lifting rotors. The airframe was all light alloy stressed-skin, the high wing having powered ailerons and plain flaps. The fuselage had a glazed nose, three – seat cockpit above the nose and a main cargo area17.9 x 3.1 x 2.8m (58′ 9" x10′ 2" x 9′ 2") for 80 seats or 16.5 tonnes of cargo. The entire nose could swing open to starboard for load­ing bulky items or a vehicle. The original pro­totype was powered by 5,900-shp TV-2VK engines, but these were later replaced by the 5,500-shp D-25VK. These had free turbines geared via a clutch to the main-rotor and via a front drive to the four-blade propeller and a fan blowing air through the oil cooler from a circular inlet above the nacelle. The two free – turbine outputs were interconnected by a 12- part high-speed shaft ‘about 20m long’. The main rotors were larger derivatives of those of the Mi-4. In helicopter mode the propeller drive was declutched and the flaps were fully lowered. Flight control was by differential cyclic and collective pitch. In aeroplane mode the lifting rotors were free to windmill and the aircraft was controlled by the ailerons and tail surfaces. The twin-wheel landing gears were fixed.

Apart from prolonged dissatisfaction with the engines, the problems with the Ka-22 were mechanical complexity, severe losses in the gearboxes and drives and the fact that each lifting rotor blew straight down on top of the wing. Similar charges could be levelled against today’s V-22 Osprey.

Purpose: To investigate the potential of a rocket-propelled interceptor.

Design Bureau: OJB-155 ofA I Mikoyan.

As a major (in most respects the greatest) pi­oneer of rocket-propelled aircraft, the Soviet Union was intrigued to capture examples of the Messerschmitt Me 163 and Me 263 (Ju248). In 1944the MiG OKB produced ‘doo­dles’ of Me 163 type aircraft, but in 1945 the bureau received a contract to build two pro­totypes of a rocket interceptor (a similar con­tract was awarded to A S Moskalyov). The MiG aircraft was designated >K, the Cyrillic character sounding like the s in ‘measure’, represented in English as Zh, and given the of­ficial designation I-270. To prepare for the air­craft’s handling qualities several OKB and NIl-WS pilots practised with a Yak-3 over­loaded by lead bars. The first I-270 was ready for flight well before its propulsion system. The rocket engine was simulated by an inert mass in the tail, but the Zh-01 was still well below normal weight because it lacked pro­pellants, armament, radio and the windmill generator, in early December 1946 VN Yuganov began testing it as a glider at speeds up to 300km/h (186mph), casting off from a Tu-2 tug. At the start of 1947 Zh-02 was ready, with propulsion, and it began testing (precise date not recorded), the assigned pilot being A K Pakhomov of the WS. On an early flight
he made a badly judged landing which dam­aged 02 beyond economic repair. A few weeks later Yuganov belly-landed 01, and again nobody bothered to repair it.

Generally similar in layout to the Ju 248, ex­cept for the prudent addition of a high-mount­ed horizontal tail, the I-270 was of course all-metal. The small wing had a laminar pro­file, fixed leading edge, slotted flaps and con­ventional outboard ailerons. Structurally it was unusual in having five spars. The tail comprised a large fin and mass-balanced rudder and a small tailplane with elevators which, like the ailerons, had bellcrank fair­ings on the underside. The circular-section fuselage had the wing amidships at mid­depth, attached from below as a single unit. The cockpit in the nose was pressurized by air bottles, and the seat could be ejected by a cordite gun. The tricycle landing gear had a track of only 1.6m (5ft Sin) despite the main wheels being inclined slightly outwards. Wheelbase was 2.415m (7ft llin), the nose unit being steerable. Each unit retracted for­wards, power for the landing gear and flaps being provided by air bottles. The rocket en­gine was an RD-2M-3V, developed by L S Dushkin and V P Glushko. The fuselage behind the cockpit was almost entirely occu­pied by four tanks housing 1,620kg (3,571 Ib) of RFNA (red fuming nitric acid) and 440kg (970 Ib) of kerosene. These were initially fed
by an electrically driven pump, of Me 163 type. As the liquids reached the chamber they were automatically ignited by injection of high-test hydrogen peroxide, of which 60kg (132 Ib) was provided in seven stainless-steel bottles. Once operating, the engine was fed by turbopumps driven by the propellants themselves. The engine had one main thrust chamber, rated at sea level at 1,450kg (3,1971b), and an auxiliary chamber rated at 400kg (882 Ib). Take-off and initial climb was normally made with both in operation, when endurance was about 41/2min. In cruising flight, with the small chamber alone in use (high-altitude thrust being about 480kg, l,0581b), endurance was 9min. An electrical system was served by a battery charged by an Me 163 type windmill generator on the nose. RSI-4 radio was fitted, with an external wire antenna, and armament comprised two NS – 23 with 40 rounds each. A plan to fit four RS- 82 rockets under the wings was not actioned.

By the time they were built these aircraft were judged to be of no military importance.

Photographs on the opposite page: Top right: Zh-01, without engine. Three views of I-270, Zh-02.

Purpose: To create a fighter with unprecedented speed.

Design Bureau: Aleksandr Sergeyevich Moskalyov, initially in Leningrad and later at the VGU and Aircraft Factory No 18, Voronezh.

Moskalyov was a talented young designer/ pilot who achieved success with convention­al aircraft, notably the SAM-5 light transport (SAM stood for Samolyot [aeroplane] Alek­sandr Moskalyov). He also persistently strove to create highly unconventional aeroplanes of tailless configurations. The first of the latter series was the Sigma, named for the letter of the Greek alphabet. He sketched this in 1933 whilst working at the Krasnyi Letchik (Red flyer) factory in Leningrad, and worked on rocket propulsion with V P Glushko in a seri­ous endeavour to design an aeroplane to reach l,000km/h (621 mph), and if possible to exceed Mach 1 (the first project in the world with this objective). When it was clear that a rocket engine with adequate thrust was many years distant, he recast the design with piston engines. He was working on this when he left Leningrad to be a lecturer at the VGU, the State University at Voronezh. Under the guid­ance of A V Stolyarov he tested models in the VGU’s newly built high-speed tunnel. In September 1934 he submitted his preliminary report on SAM-4 to the GlavAviaProm (direc­torate of aircraft industries), whose Director, 11 Mashkevich, berated Moskalyov for sub­
mitting such ‘unimaginable exotics’.

By 1933 Moskalyov had decided a suitable configuration for a fast aircraft was an all­wing layout with a ‘Gothic delta’ plan shape, with trailing-edge elevens and Scheibe sur­faces (fins and rudders on the wingtips). The drawing shows two main wheels in the front view, but this may be an error as Moskalyov favoured a single centreline gear and, as shown, skids on the wingtip fins. The drawing shows a single propeller, but in fact Moskaly-
ov intended to use two Hispano-Suiza 12 Ybrs engines, each of 860hp (these were later made in the USSR under licence as the M-100), driving separate contra-rotating pro­pellers. The stillborn rocket version would have had a prone pilot, but the piston-en­gined SAM-4 featured a conventional en­closed cockpit; the designer did not explain why this was offset to port.

This proposal was altogether too ‘far out’ for Mashkevich. No data survives.

Purpose: To test an aeroplane with landing gears on the centreline.

Design Bureau: S A Moskalyov at VGU and GAZNolS.

Unaware of the fact that Bartini had already flown the Stal’-6 (see page 16), Moskalyov de­cided in 1933 that it would be prudent to build a simple low-powered aeroplane to investi­gate the landing gear he proposed to use for his fighter, with a single mainwheel and skids under the wingtips and tail. It was flown in early 1934, but later in that year it was modi­fied into the SAM-65/s.

The SAM-6 had a conventional tail, though its moment arm was very short and the air­craft was dominated by its relatively huge wing. The structure was wood, with fabric – covered control surfaces. The engine was a three-cylinder M-23 rated at 65hp. Behind the small fuel tank was the open cockpit. The Scheibe fins were not fitted with rudders, and were described by the designer as ‘plates’. Initial testing was done in early 1934 on centreline tandem skis. Later the front ski was replaced by a wheel on a sprung leg in­side a trouser fairing. After rebuilding as the SAM-66/s testing continued in 1935. This had tandem cockpits with hinged hoods, and in its final form a conventional landing gear was fitted with two trousered mainwheels.

According to Shavrov ‘experiments showed that the centreline gear was quite practical’. Moskalyov intended to use such landing gear on the SAM-7, but ultimately decided not to (see original drawing of that aircraft). The fol­lowing specification refers to the SAM-6t»/s.

Top right: SAM-6.

Purpose: To build a superior two-seat fighter.

Design Bureau: A S Moskalyov, at GAZ No 18, Voronezh.

In 1934 Moskalyov was engaged in engineer­ing later versions of TB-3 heavy bomber for production. This enabled him to use one of this bomber’s engines and propellers to power a fighter (though it was hardly ideal for the purpose). Despite the fact that it was far more complex than any of his previous air­craft, and also had advanced all-metal con­struction, the SAM-7 was completed in October 1935. Pilots considered it potentially dangerous, and factory testing was confined to taxying at progressively higher speeds, ulti­mately making short hops in a straight line.

The SAM-7’s configuration was described by Shavrov as ‘one of the world’s most un­
orthodox’, but in fact the wing was of fairly normal design, with straight equal taper and an aspect ratio of 4.6. Aerofoil profile was R – II, and the thickness/chord ratio 12 per cent, without twist. Apart from this the Sigma (the designer’s second use of this name) was in­deed unconventional. There was no tail. On the wingtips were Moskalyov’s favoured Scheibe fins, fitted with fabric-covered horn – balanced rudders. On the wing trailing edge were outboard ailerons and inboard eleva­tors which, when depressed to a slight angle, were intended also to serve as slotted flaps (though it is difficult to see how they could do so without putting the aircraft into a dive). The main landing gears had single struts, raked forward, with a track of 2.8m (9ft 2in), and were pivoted to the front spar to retract inwards. The surviving drawing shows a tail – wheel, but Shavrov says there was a non-cas-
toring tailskid. The structure was almost wholly Dl duralumin, the maximum wing skin thickness being 2.5mm. The nose inlet served the carburettors. The 830hp M-34 en­gine drove a four-blade wooden propeller, and was cooled by a surface evaporative (steam) system similar to that of the Stal’-6. For use at low speeds a normal honeycomb radiator could be cranked down behind the cockpit. The intended armament was two ShKAS fixed above the engine, fired by the pilot, and a second pair mounted on a pivot and aimed by the rear gunner.

One cannot help being astonished that Moskalyov was able to obtain funds to build this aircraft, because there is no mention of any official approval of the design (which would almost certainly have been refused). One feels sympathy with the test pilots, who were probably right to be hesitant.

Original OKB drawing of SAM-7.

Purpose: To test at modest speeds an aircraft with a ‘Gothic delta’ wing of very low aspect ratio.

Design Bureau: A S Moskalyov, from 1936 head of his own OKB-31 at Voronezh.

Always eager to build his incredible SAM-4 dart-like fighter, Moskalyov was rebuffed in these efforts until in 1936 US magazines fea­tured futuristic fighters with low-aspect-ratio wings, shaft drives and prone pilots. This spurred GUAP to invite Moskalyov at least to try out his radical ideas with a simple aircraft with an engine of modest power. Following tunnel tests by V P Gorskiy at CAHI (TsAGI), the SAM-9 was built in 70 days, and flown on skis in early 1937 by N S Rybko at Voronezh. Following six flights by Rybko and A N Gusarov, it was taken to Moscow and tested in short hops by Rybko and A P Chernavskii, finally making eight full flights in the hands of Rybko. The aircraft was tricky, demanding an angle of attack of 22° at take-off and landing, and being unable to climb higher than 1,500m (4,921ft). Despite this the NKAP (state com­missariat for aviation industry) suggested that Moskalyov should produce a fighter with a 0.975 aspect ratio wing, and this led to the RM – l. SAM-29.

The SAM-9 Strela (Arrow) was made of wood, with a brilliant surface finish, the cable-operated rudder and elevons having fabric covering. The thick aerofoil was of RAF.38 profile, with local modifications. The cockpit was placed between the two main spars, with a hinged canopy. The engine was a Renault MV-4 aircooled inverted 4-cylinder rated at 140hp. The neat main landing gears had pivoted rubber-sprung cantilever legs for skis or wheels, and the tailskid did not castor. The rudder and broad-chord elevons had trim tabs.

Without the support of CAHI (TsAGI) and the (mistaken) belief that such aircraft were planned in the USA, this project would prob­ably have got nowhere. As it was, the SAM-9 merely showed that such aircraft could fly,

but with difficulty. In a recent display ofmod – els of Moskalyov aircraft the SAM-9 was de­picted entirely doped red except for the propeller blades, and with a placard giving speed and altitude as 340km/h and 3,400m.

Purpose: To design a small fighter with ‘push/pull’ propulsion.

Design Bureau: A S Moskalyov, OKB -31 at Voronezh.

This small fighter was unconventional in lay­out, but used an ordinary wing, and had noth­ing to do with the designer’s previous fighter concepts. According to Shavrov ‘Fokker de­signed an almost exact copy of the SAM-13, known as the D.23…’ In fact it was the other way about, because Moskalyov began this de­sign in 1938, immediately after the D.23 had been exhibited at the Paris Salon. The single prototype was first flown by N D Fikson in late 1940, 18 months after the Dutch fighter, and proved difficult to handle, to need inordinate­ly long runs to take off and land, and to have a sluggish climb and poor ceiling. Its designer worked round the clock to improve it, and by
spring 1941 it was undergoing LII testing in the hands of Mark L Gallai. Apart from the fact the nose gear never did retract fully, it was by this time promising, and it was entered for the summer high-speed race, but the German in­vasion on 22nd June stopped everything. The No 31 OKB was evacuated, but this aircraft had to be left behind so it was destroyed. The OKB documents have not been found.

The SAM-13 was powered by two 220hp Renault MV-6 inverted six-cylinder aircooled engines driving 2.2m (7ft 21/2in) two-blade variable-pitch propellers. Between them was the pilot, and Moskalyov fitted the rear pro­peller with a rapid-acting brake to make it safer for the pilot to bail out. The small two – spar wing was sharply tapered, and was fitted with split flaps inboard of the booms carrying the single-fin tail. Apart from welded steel – tube engine mounts, the structure was wood­
en, with polished doped ply skin. The main landing gears retracted inwards and the nose unit aft. One drawing shows the nose unit (which had a rubber shimmy damper) to have had a levered-suspension arm for the axle. The intended armament, never fitted, comprised four 7.62mm ShKAS, two above the front engine and two at the extremities of the wing centre section.

Moskalyov knew that the MV-6 was avail­able for licence-production in the USSR, and thought this aircraft might make good use of some. Even had the programme continued without interruption it is hard to envisage the SAM-13 being adopted by the WS.

Purpose: To renew attempt to build a rocket-engined interceptor.

Design bureau: A S Moskalyov, No 31.

During the Great Patriotic War practical rock­et engines for manned aircraft became avail­able. Moskalyov never forgot that he had been invited by the NKAP to build a fighter with the so-called Gothic delta wing of 0.95 aspect ratio. In 1944, despite much other work, he collaborated with L S Dushkin in planning what was to be the ultimate Strela
fighter. This time most of the technology ex­isted, and S P Korolyov lent his support, but once the War was over such a project was judged to be futuristic and unnecessary. Moskalyov’s OKB was closed in January 1946, and he returned to lecturing, but he contin­ued to study this project for two further years.

The final SAM, also called Raketnyi Moska – lyov, would have followed the usual Strela form in having a Gothic delta wing and no horizontal tail. The wing was fitted with elevens and blended into a needle-nosed
fuselage carrying a large fin and rudder. The Dushkin RD-2M-3V engine, rated at 2,000kg (4,409 Ib) thrust at sea level and much more at high altitude, was installed at the rear and fed with propellants from tanks filling most of the airframe. Two cannon would have been installed beside the retracted nose landing gear.

This was yet another of this designer’s near misses, all of which stemmed from his abun­dance of enthusiasm.

No data survives.

Purpose: To create a mixed-power (piston engine plus rocket) fighter.

Design Bureau: OKB of Pavel Osipovich Sukhoi, Moscow. Note: this aircraft was not related to the later Su-7 jet fighter.

Having in 1941 seen the Su-2 attack bomber accepted into production, Sukhoi subse­quently never dislodged the IL-2/IL-10, de­spite the excellence of different versions of
was replaced by a single-seat cockpit with a unged canopy with a fairing behind it. An ad­ditional fuel tank replaced the internal weapons bay, and the large-calibre wing guns were removed, the armament being three synchronized ShVAK 20mm cannon each with 370 rounds. At first the ASh-71 type engine was retained, but this was soon re­placed by a smaller and less-powerful ASh – 82FN, rated at l,850hp on 10o-octane fuel driving an AV-9L four-blade propeller. In 1944 aTK-3 turb o sup ercharger was added on each side, and an RD-lKhZ rocket engine was in­stalled in a new extended tailcone. As de­scribed previously, this Dushkin/Glushko engine had a single thrust chamber burning the same petrol (gasoline) as the piston en­gine, which ignited hypergolically (instant re­action) when mixed with RFNA (red fuming nitric acid). The acid was housed in an addi­tional tank behind the cockpit, with access through a dorsal hatch. This tank gave a con­tinuous burn time of about four minutes. When rocket power was selected, the pro­pellants were fed at a rate of 1.6kg (3.5 Ib) per second, giving a thrust of300kg (661 Ib) at sea level and about 345kg (761 Ib) at high altitude.

By 1945 this aircraft was no longer compet­itive, and the rocket engine never went into production. In any case, during a practice for the first post-war air display in late 1945 the rocket engine exploded, casing a fatal crash.

3,250kg 7,1651b

480/50/1 80 1,058/110/397Ib

4j36°kg 9,612 Ib

Performance Maximum speed at sea level (no rocket) 480 km/h at 7.5 km (24,600 ft) with rocket 680 km/h at 12 km (39,370 ft) with rocket 705 km/h Service ceiling 12,750m Range (with full rocket bum) 800 km Take-off 300 m Landing speed/ 125 km/h 350m

298 mph 423 mph 438 mph 41,831 ft 497 miles 984ft 78 mph 1,148ft

For interest, drawings are reproduced here of various projects which stemmed from the RSR. The first shows the way CAHI (TsAGI) wanted it. The purist aerodynamicists in that establishment were convinced that this su­personic-cruise aircraft ought to have true su­personic wings, with sharp edges and a trapezoidal (parallel double wedge) profile instead of a traditional curved aerofoil. As this would have meant a very long take-off run they proposed to add substantial wings out­board of the engines, giving a span of 14.5m (47ft 6%in), requiring total redesign and a dra­matically inferior aircraft. The next drawing shows the awesome A-57, proposed in 1957 by R L Bartini, who featured on previous pages. There were several versions of this and the considerably smaller Ye-57. The A-57 shown would have been powered by five Kuznetsov NK-10 engines, each of 25,000kg (55,115 Ib) thrust. This 320 tonne (705,467 Ib) vehicle, with a length of 69.5m (228ft) and wing area of 755m2 (8,127ft2), was to have been water-based for operational flexibility and to avoid having to use vulnerable airfields (though it also had skids for airfield landings if necessary). It would have carried a 244N thermonuclear bomb internally, as well as a 2RS (later RSR) carried pick-a-back to the tar­get at 2,500km/h (l,553mph, Mach 2.35) to serve as an accompanying reconnaissance aircraft. Together they could cover targets within a radius of 5,000km (3,107 miles), the Tsybin 2RS reconnaissance vehicle using its fuel only on the return flight. The final draw­ing shows the Tsybin RGSP, also dating from 1957. This too would have been water-based, with a planing bottom, engines moved above the wings to avoid the spray (minimised by the down-angled water fins), and with the ex­ternal tanks serving as wingtip buoyancy bod­ies. This version was not equipped for airfield landings.

Purpose: To build an improved fighter armed with APK-4 guns.

Design Bureau: Brigade led by Viktor Nikolayevich Chernyshov inAGOS (Department of Aeroplane and Hydroplane Construction), whose Chief Constructor was A N Tupolev.

Towards the end of the 1930s there was great activity in the still chaotic aircraft industry of the embryonic Soviet Union. Part of this ef­fort was concerned with making use of the large-calibre recoilless guns devised by L V Kurchevskii. These had various designations
but the most common was APK (Avto – matichyeskaya Pushka Kurchevskogo, auto­matic cannon Kurchevskii). Such guns were invented by Cdr Cleland Davis, ofthe US Navy, and developed in England from 1915. The idea was that, if the recoil of the projectile could be balanced by a blast of gas and pos­sibly an inert mass fired to the rear, then air­craft could use lightly made weapons of large calibres. Russian copies were produced by Professor B S Stechkin in 1922-26, and in 1930 Leonid Vasil’yevich Kurchevskii restarted this work and developed a range of weapons of different calibres. Of these the most immedi-

ately important was the APK-4, with a calibre of 76.2mm (Sin). Together with the Grig – orovich Z (later I-Z) described earlier, the ANT-23 was the first aircraft specially de­signed to use these guns. The AGOS design­ers had the idea that, instead of just hanging the guns under the wings, they could be put inside strong tubes which could then attach the tail to the wing. This enabled the central nacelle to have an engine at each end, giving outstanding flight performance. Design began in June 1930, and the first flight was made by Ivan Frolovich Kozlov on 29th August 1931. On 21st March 1932 he was

undertaking firing trials at about 1,000m (3,280ft) when the diffuser section at the rear of the left gun exploded. This severed the tail controls in that boom, but he managed to make a normal landing, the boom collapsing during the landing run (he received the Order of the Red Star). The fault was soon correct­ed, and from autumn 1931 a second proto­type (called a doobler), the ANT-236/s, was built. This received service designation I-12, and was also named Baumanskii Komsomo – lets after the revolutionary who until his death in 1905 had worked next to the AGOS site. It incorporated various minor improvements, one of which was to arrange for the pilot in emergency to detonate a charge which sev­ered the drive shaft to the rear propeller prior to baling out. Work was halted during the in­vestigation into the accident to the first air­craft, and by 1933 the I-12 was overtaken by the Grigorovich IP family and the DIP, ANT-29. Work on it was stopped on 1st January 1934.

Structurally the ANT-23 followed Tupolev tradition in that it was a cantilever monoplane made entirely ofaluminium alloy, but it broke new ground in that corrugated sheet was not used except on the fin and rudder. Instead, the central nacelle had smooth skin, and the wings were skinned in sheets cut to a uniform
width of 150mm (Gin), wrapped round the leading edge. The edge of each strip was rolled to have a channel section, so that the complete wing appeared to have a skin with widely spaced corrugations. In usual Tupolev fashion, the aileron chord extended behind the trailing edge ofthe wing. The nacelle was welded from KhMA steel tube, with much of the light-alloy skin being in the form of de­tachable panels. At each end was an import­ed 480hp Gnome-Rhone GR9K (licence-built Bristol Jupiter) in a cowling with helmets over the cylinders. Above each wing was attached a precision-made tube of high-strength steel formed by screwing together three sections each machined to an internal diameter of 170mm (6%in). Wall thickness varied from 1 to 3mm. Over the wing the tube was faired in by thin aluminium sheet, and at the tail end was a gas diffuser. Above this was a shallow platform to which was attached the tailplane, carrying the strut-braced fin in the centre. Tall sprung tailskids were attached under each tube, and originally the rubber-sprung main landing gears had spats, though these were later omitted. Inside each tail boom was in­stalled the 76.2mm APK-4, with the front of the barrel projecting. Soon the engines were replaced by the 570hp version made under
licence in the Soviet Union as the M-22, and the helmets were incorporated into ring cowls. Another modification was to replace the ver­tical tail by a redesigned structure with the same kind of skin as the rest of the aircraft.

When work began it was thought that this aircraft might be a world-beater. It was soon evident that the performance was well short of expectations, partly because ofthe fact that the rear propeller worked in the slipstream of that in front. Perhaps the greatest shortcom­ing of this aircraft was the fact that the am­munition supply for each gun was limited to two rounds.

Purpose: A heavy fighter with large-calibre recoilless guns.

Design Bureau: KOSOS-CAHI (department of experimental aeroplane construction, central aero-hydrodynamics institute), Chief Constructor A N Tupolev.

This large fighter was a natural successor to the ANT-21 MI-3 (MI = multi-seat fighter) or­dered in January 1932 and flown in May 1933. Whereas that aircraft had had conventional armament, the ANT-29 or DIP (Dvukhmestnyi Istrebitel’ Pushechnyi, two-seat cannon [armed] fighter) was designed around two of the largest available calibre of APK recoilless guns (see preceding story). Funds for a single prototype were made available by the WS in September 1932. Tupolev entrusted the de­sign to his first deputy P O Sukhoi. Normally the aircraft would have flown in about a year, but priority was given to the ANT-40 fast bomber (which flew in 1934 as the SB), and the ANT-2 9 was not completed until February 1935. Flight testing was started by S A Korzin – shchikov, who reported that the flight con­trols, especially the ailerons and rudder, were unacceptably ineffective. This prototype was returned to CAHI’s ZOK (factory for prototype construction) for rectification, the main task being to re-skin the control surfaces. Testing resumed in late 1935, but by this time the ANT-46 (DI-8) was flying. The ANT-29 be­longed to the previous generation, and it was abandoned in March 1936.

Like its predecessor, the ANT-21, the ANT – 29 was an aerodynamically clean monoplane powered by two liquid-cooled engines. The wings were aerodynamically similar but to­tally different structurally, and the engines likewise were quite new. They were two of the first 760hp Hispano-Suiza 12Ybrs 12-cylin­der engines to be imported into the Soviet Union. Later this engine was developed by VYaKlimov into the VK-103 and VK-105, of which over 129,000 were constructed. In this aircraft they drove imported French Chau – viere three-blade variable-pitch propellers of 3.5m (138in) diameter. Carburettor air en­tered through a small inlet under the wing leading edge, and the radiator was in a shut­ter-controlled duct directly under the engine. The wing had a modern structure with two plate spars, made as a 3m (9ft 1 0in) horizon­tal centre section and 5.9m (19ft 4in) outer panels with taper and dihedral. Like the rest of the airframe the outer wing skins were smooth. In this Sukhoi broke new ground, previous ‘ANT’ aircraft having had corrugated metal skins showing that they originated in Junkers technology of the early 1920s. The short fuselage was of tall oval section and

seated the pilot in the nose under a rearward – sliding canopy and a backseater over the trail­ing edge under a forward-sliding canopy (as in early versions of the SB). The backseater would have worked radio had it been fitted, but his main task was to check the automatic reloading of the guns and clear stoppages. The wings were fitted with large two-part ailerons and split flaps, while the tail carried the wire-braced tailplane high up the fin, the elevators and rudder having large Flettner (servo) tabs. Like the ANT-21 and SB, the main landing gears had single shock-struts with a fork carrying the axle for a braked wheel with a 900 x 280mm tyre which, after retraction to the rear, partially projected to minimise damage in a wheels-up landing. At the rear was a large tailskid. Main-gear re­traction, like flap operation, was hydraulic. The primary armament comprised two APK – 8 recoilless guns, also known as DRP (Dy – namo-Reaktivnaya Pushka), mounted one above the other. The feed was via two chutes on opposite sides of the fuselage. Each gun
had an unrifled barrel about 4m (13ft lin) long, with a calibre of 102mm (4in). The firing chamber was connected at the rear to a re­coil tube terminating in the recoil-cancelling divergent rear nozzle, extended a safe dis­tance behind the rudder, through which pro­pellant gas blasted when each round was fired. Sighting was done with an optical sight in a prominent fairing ahead of the wind­screen, and could be assisted by firing tracer from two 7.62mm ShKAS machine guns in the wing roots (these are shown in Shavrov’s drawings, but unlike the main armament they do not appear ever to have been installed). It was intended also to fit a pivot-mounted ShKAS in the rear cockpit. There was no pro­vision for a bomb load. Arguments over ar­mament continued, but no attempt was made to test the ANT-29 with the alternative forward-firing armament ofa20mm ShVAK in each wing root.

By the time it was on test this was no longer an important aircraft, and (for reasons not recorded) it failed NIl-WS testing.

Purpose: An improved heavy fighter with large-calibre recoilless guns.

Design Bureau: KOSOS-CAHI, chief constructor A N Tupolev, who assigned this aircraft to A A Arkhangel’ skii.

This aircraft was a derivative of the SB (ANT-40) fast bomber. The single prototype was ordered in November 1934, on condition that the SB (the first prototype of which had flown a month previously) had priority and would not }n any way be delayed. The DI-8 was created quickly and was flown by Yu A Alekseyev on 1 st August (also reported as 9th August) 1935. Factory testing was con­tinued to June 1936, but the ‘liquidation’ of

Kurchevskii’s gun bureau and the arrest for treason and spying of Tupolev halted the pro­gramme.

Until recently little was known about the ANT-46, and only one photograph had been discovered. This did not show the nose clear­ly, and published accounts stated that the ANT-46 was based on the SB but had a metal­skinned nose containing machine guns. It is now known that it had a glazed nose identi­cal to that of the bomber. Instead of being a two-seat aircraft it also had a navigator/ bomb-aimer in the nose, and an internal bomb bay (for example, for eight FAB-100 bombs) with bomb doors. The interesting feature was that incorporated in each wing
outboard of the fuel tanks, between the split flaps and the ailerons, were single DRP (APK – 11) recoilless guns, each fed by an automati­cally indexed supply of 45mm (IXin) ammunition, the rear blast tubes projecting behind the trailing edge. Like the first SB the fin and rudder had a squared-off top, and the engines were not as previously thought GR14s but, as on the first SB, nine-cylinder Wright Cyclones of 710hp, driving Hamilton two-blade propellers. Like the ANT-29, this aircraft carried CAHI titles and the ANT num­ber 46 on the tail.

This aircraft fulfilled expectations, but was considered an outdated concept.

Purpose: Originally, fast passenger transport; later, long-range experimental aircraft.

Design: SNII GVF; construction at GAZ (Factory) No 81, Moscow Tushino.

In the winter 1933-34 the GUGVF (chief ad­ministration of the civil air fleet) issued a re­quirement for a fast transport aircraft to carry 10 to 12 passengers. Curiously, the two proto­types built to meet this demand were both the work of immigrant designers, the Frenchman Laville (with ZIG-1) and the Italian Bartini. The latter had already produced drawings for a transport to cruise at 400km/h (248mph), which was well in advance of what the GVF had in mind. Always captivated by speed, Stalin decreed that a bomber version should be designed in parallel. Still in charge of de­sign at the SNII GVF, Bartini refined his study into the Stal’-7, the name reflecting its steel construction.

Strongly influenced by the Stalin decree, Bartini created a transport notable for its cramped and inconvenient fuselage, highly
unsuitable for passengers but excellent for bombs, and for long-range flight. The original structure was to be typical Bartini welded steel-tube trusses with fabric covering, but the stress calculations were impossibly diffi­cult, with 200 primary rigid welded intersec­tions between tubes of different diameters. In late 1934 the fuselage was redesigned as a light-alloy stressed-skin structure, with sim­pler connections to the unchanged wing.

Only one aircraft was built, in the work­shops ofZOK, the factory for GVF experimen­tal construction. The first flight was made on an unrecorded date in autumn 1936, the pilot being N P Shebanov. Performance was out­standing, and Shebanov proposed attempting a round-the-world flight. In 1937 the StaP-7 was fitted with 27 fuel tanks with a total ca­pacity of 7,400 litres (1,628 Imperial gallons, 1,955 US gallons). A maximum-range flight was then attempted, but – possibly because of structural failure of a landing gear – the air­craft crashed on take-off. Bartini was arrest­ed, and was in detention (but still designing, initially at OKB-4, Omsk) for 17 years.

The aircraft was repaired, and on 28th Au­gust 1939, at a slightly reduced weight, suc­cessfully made a closed-circuit flight of 5,068km (3,149 miles) in 12hrs Slmin (aver­age speed 404.936km/h, 251.62mph), to set an FAI Class record. The route was Moscow Tushino-Maloe Brusinskoe (Sverdlovsk re – gion)-Sevastopol-Tushino, and the crew comprised Shebanov, copilot VAMatveyev and radio/navigator N A Baikuzov. In Bartini’s absence, the project was seized by his op­portunist co-worker V G Yermolayev, who re­designed it into the outstanding DB-240 and Yer-2 long-range bomber.

The wing was typical Bartini, with pro­nounced straight taper and construction from complex spars built up from multiple steel tubes, almost wholly with fabric covering. Each wing comprised a very large centre sec­tion, with depth almost as great as that of the fuselage, terminating just beyond the engine nacelles 2.8m (9ft 2/4in) from the centreline, with sharp anhedral, and thinner outer panels with dihedral. The trailing edges carried split flaps and Frise ailerons, the left aileron having

a trim tab. One account says that the inverted – gull shape ‘improved stability and provided a cushion effect which reduced take-off and landing distance’, but its only real effect was to raise the wing on the centreline from the low to the mid position.

This was just what the fuselage did not need, because the massive deep spars formed almost impassable obstructions and eliminated any possibility of using the aircraft as a passenger airliner. The fuselage was a light-alloy structure, with an extremely
cramped cross-section with sides sloping in towards the top (almost a round-cornered tri­angle). Entry was via a very small door on the left of the rear fuselage. The cockpit in the nose seated pilots side by side, and had a glazed canopy with sliding side windows and the then-fashionable forward-raked wind­screen. Immediately behind the cockpit there was a station for the navigator/radio operator. The tail surfaces, made of dural/fabric, were of low aspect ratio, the elevators having tabs.

The engines were the 760hp M-100, these being the initial Soviet licence-built version derived by V Ya Klimov from the Hispano – Suiza 12Ybrs. They were installed in neat cowlings at the outer ends of the centre sec­tion, angled slightly outwards and driving pro­pellers with three metal blades which could have pitch adjusted on the ground. One ac­count states that wing-surface radiators were used, but it is obvious from photographs that ordinary frontal radiators were fitted, as in the Tupolev SB bomber. Plain exhaust stubs were fitted, though this may have scorched the wing fabric and one drawing shows ex­haust pipes discharging above the wing. In the course of 1938-39 the original engines were replaced by the derived M-103, rated at 860hp, which improved performance with heavy fuel loads. A hydraulic system was pro­vided to operate the flaps and the fully re­tractable main landing gears, each unit of which had a strong pair of main legs which hinged at mid-length, the unit then swinging back on twin forward radius arms (like a DC – 3 back-to-front). The castoring tailwheel was fixed. In the nose were twin landing lights.

The Stal’-7 was simply a sound aeroplane able to fly at what was in its day a very long way at high speed. As a transport it was in­convenient to the point of being useless, though it was supposed to be able to seat 12 passengers, and it was flawed by its basic lay­out and structure. The Soviet Union was right to take a licence for the Douglas DC-3. On the other hand, Yermolayev transformed the Stal’-7 into an outstanding long-range bomber.

Left: Two views of Stal’-7.

Purpose: To continue stratospheric-flight research with an aircraft superior to BOK-1. Design Bureau: Bureau of Special Design, Smolensk. Chief designer Chizhevskii.

Design of this aircraft began in 1936. The Tupolev RD was again used as the starting point, but with features intended to enable greater heights to be reached. The test pilots were Petrov and Stefanovskii. According to Shavrov the BOK-7 was first flown in 1938, and ‘showed the same characteristics as the BOK-1’. Several two-man crews, including such important long-distance pilots as Gro­mov, Yumashev, Danilin, Spirin, Baidukov, Belyakov and others, spent periods of several days sealed in the GK checking all aspects of human life in preparation for proposed high- altitude long-distance flights in the BOK-15. According to some historians the ultimate ob­jective was a high-altitude circumnavigation, and that the by-function designation of this aircraft was K-17, from Krugosvetnyi (round the world). Photographs originally thought to be of the BOK-7 are now known to show the BOK-11.

The BOK-7 had the full-span wing of the RD, and aft-retracting landing gears, but com­pared with the RD the legs were redesigned for much lighter gross weight, and fitted with single wheels. Attention was concentrated on the fuselage, which unlike the BOK-1 had the GK (pressure cabin) integral with the air­frame, the centre fuselage being a slim cylin­der sealed by gaskets and adhesives, and with grommets fitting round the control wires and other services passing through apertures in the wall. The normal oxygen supply to the pilot and pilot/observer ‘compensated for the insignificant amount of air escaping’. The sealed drum was fitted with two hemispheri­cal domes, the front with eight and the rear with six transparent portholes so that the oc­cupants could see out, with a better view than from the BOK-1. The GK was kept at pressure by a tapping from a centrifugal PTsN (super­charger) blower driven by step-up gears from the engine. The engine was an 890hp M-34FRN fitted with two TK (turbosuper­chargers). It is probable that these delivered compressed air to the PTsN which then fed the engine, the cabin supply being taken off a small bleed pipe. Shavrov states that ‘all sys­tems worked well’, and that the experiments were ‘very interesting’.

According to Shavrov this aircraft had ‘the first GK of the combined type’ with both a sealed compartment kept under pressure and an oxygen supply. Some accounts state that AI Filin at the NIl-WS worked out details of the proposed circumnavigation, in 100- hour stages, but that the project was aban­doned after he was arrested in 1939 and executed in Stalin’s Terror of 1940. This air­craft led to the BOK-8, BOK-11 and BOK-15, but it appears that no illustrations of it have been discovered.

Purpose: To create a light transport with minimum operating cost.

Design Bureau: Kharkov Aviation Institute, Aviavnito brigade led by Aleksandr Alekseyevich Lazarev.

In the 1930s several Soviet designers pro­duced aircraft intended to demonstrate how much could be transported on the l00hp of an M-l 1 engine. These aircraft were as a class called Planerlyet (motor glider). This exam­ple had an unconventional configuration. It first flew on 14th September 1936, dual-con­trolled by V A Borodin and E I Schwartz. Eventually a control linkage was found which by 27th September enabled good turns to be made. Shavrov’s account ends with The

overall conclusion of the tests at Nil GVF (civil aviation test institute) was extremely posi­tive’, but nothing came of this one-off.

The Aviavnito-3 (often incorrectly called KhAI-3) was essentially an all-wing aircraft. The wing comprised a rectangular centre sec­tion, with the uncowled engine mounted on steel tubes on the front, to which were bolted two outer panels tapered on the leading edge. Aerofoil was V-106, with a t/c ratio of 14 per cent over the centre section, which had a chord of 5.0m (16ft Sin), tapering to 7 per cent at the tips, which incorporated 8° washout. Structurally, the centre section was KhMA steel tube covered by Dl Dural skin, while the outer panels were all wood, with truss ribs supporting closely spaced stringers. Along each outer edge of the centre section was a row of four seats, each front seat being for a pilot (the two pilots had to agree in advance which one should do the flying), covered by a row of sliding canopies. The flight controls comprised large unbalanced cable-operated surfaces divided into inner and outer sections to serve as ailerons and elevators. In addition, spoilers were recessed into the upper surface of each wingtip, driven by the pedals, to en­able co-ordinated turns to be made. A 2m2 (21.5ft2) fin and rudder were added, but it was hoped eventually to do without this. The sim­ple rubber-sprung main landing gears had 800 x 150mm tyres with brakes, and the large tailwheel could castor ±25°. Between the
rows of seats were four Dl tanks giving an 8-hour endurance. During development two additional seats were inserted on each side, pushing the pilots into noses projecting ahead of the wing. To balance these the vertical tail was significantly enlarged.

It is clear that this machine did everything expected of it, and that it was eventually de­veloped to fly safely and controllably. How­ever, even though they were much faster than anything else over vast areas devoid of sur­face transport, nothing came of the rash of Planerlyet designs.

Purpose: To test the guidance system of a cruise missile.

Design Bureau: OKB-155 ofAI Mikoyan.

In late 1947 the Kremlin ordered the develop­ment of a large cruise missile which could be launched (primarily against ships) from the Tu-4. Because of the importance of this pro­ject it was assigned to a joint team formed by OKB No 155 (MiG) and a new semi-political group called SB-1 (Special Bureau Nol). The OKB assigned one of the founders, M I Gure­
vich, as titular head, but the Chief Designer was A Ya Bereznyak who has figured previ­ously on page 29 of this book. Head of SB-1 was S L Beria, son ofthe formidable Politburo member who in 1953 succeeded Stalin. In fact, SB-1 faded from the scene, as it had little to contribute, though it did have P N Kusenko as Chief Designer. Under intense pressure a swept-wing turbojet-engined missile was created, which later went into production as the KS-1 Komet. In early 1949 its guidance sys­tem was tested in an Li-2 (Soviet derivative of
the DC-3), and later in that year a more repre­sentative system was tested in the FK (also called MiG-9L, Laboratoriya). This was too large to be carried aloft by a Tu-4, so it for­mated with the Tu-4 parent aircraft and thence simulated the missile on its flight to the target. Subsequently this aircraft was used to test different cruise-missile guidance systems, assisted by the K-l, a manned ver­sion of the KS-1 missile.

Aircraft FK was a modified MiG-9 twin-jet fighter, the first type of turbojet aircraft to fly in

the Soviet Union. Features included a straight-tapered wing oflaminar profile of9% thickness with large slotted flaps and Frise ailerons, a pressurized cockpit ahead of the wing, a ground-adjustable tailplane mounted part-way up the fin, a nosewheel retracting forwards and main landing gears retracting outwards, and a nose inlet feeding air to two RD-20 turbojets (Soviet copies of the German BMW 003A, each rated at 800kg, l,7641b, thrust) mounted under the wing with jet noz­zles under the trailing edge. The final produc­tion series had an ejection-seat, and the FK was from this batch. The heavy nose arma­ment of three NS-23K guns and all armour
were removed, and the fuselage was extend­ed by splicing in an extra section accommo­dating an unpressurized rear cockpit with a side-hinged canopy for the guidance-system operator. As in the Komet, the missile’s radar dish antenna was mounted above the nose, and a receiver antenna was mounted on the leading edge of each wing. Above the fin was a streamlined container housing the aft-fac­ing transmitter and receiver antennas for the radio-command guidance from the parent aircraft after launch. Once the autopilot had set the correct course the nose radar homed on the parent’s radar signals reflected back from the target. Nearer the target the missile’s
own radar became active, steering by signals received by the leading-edge antennas.

So far as is known, the FK played a valuable role in the development of one of the world’s first turbojet cruise missiles. So did the KSK, a piloted version ofthe missile itself.

Dimensions (FK)

Span 10.0m 32ft9Kin

Length 10.12m 33 ft 2 in

Wing area 18.2m2 195.9ft2

No other data.

Purpose: To design a long-range supersonic bomber.

Design Bureau: OKB-23 of Vladimir Mikhailovich Myasishchev, Moscow.

In 1955, when the Myasishchev OKB was still striving to develop the huge 3M subsonic bomber, this design bureau was assigned the additional and much more difficult task of creating a strategic bomber able to make dash attacks at supersonic speed. The need for this had been spurred by the threat of the USAF Weapon System 110, which materi­alised as the XB-70. The US bomber was de­signed for Mach 3, but in 1955 this was considered an impossible objective for the Soviet Union. From the outset it was recog­nized that there could be no question of com­peting prototypes from different design teams. Even though the Myasishchev OKB was already heavily loaded with completing development of the huge M-4 strategic bomber and redesigning this into the 3M pro­duction version, this was the chosen design bureau. In partnership with CAHI (TsAGI), wind tunnels were built for Mach 0.93,3.0 and 6.0. The two partners analysed more than 30
possible configurations, initially in the Izdeliye (product) ’30’ family (VM-32, tailless VM-33 and VM-34). The basic requirement was finally agreed to specify a combat radius not less than 3,000km (1,864 miles) and if possible much more, combined with a dash speed (with engine afterburners in use) of Mach 2. This demanded an upgraded aircraft, and the result was the ’50’ series, starting with the M-50. Under chief designer Georgi Nazarov this was quickly accepted, and the initial programme comprised a static-test specimen and two flight articles, comprising one M-50 followed by an M-52. OKB pilots N I Goryainov and A S Lipko flew the M-50 on 27th October 1959. Modified with afterburn­ing inboard engines, it continued testing in late 1960, but was by this time judged to be of limited value, and to be consuming funds needed for ICBMs (intercontinental ballistic missiles) and space projects. The OKB-23 was closed, and its personnel were trans­ferred to V N Chelomey to work on ICBMs and spacecraft. Myasishchev was appointed Director of CAHI. To the protestations of some, the virtually complete M-52 was scrapped, and six later 50-series projects re­
mained on the drawing board. However, for propaganda purposes the M-50 was kept air­worthy and made an impressive but rather smoky flypast at the Aviation Day parade at Moscow Tushino on 9th July 1961, naturally causing intense interest in the West. After being photographed with different paint schemes, and the successive radio callsigns 022, 023,12 and 05, it was parked in the nose – high take-off attitude at Monino.

Apart from the totally different wing, in overall configuration, size and weight the M-50 exactly followed the M-4 and 3M family. Despite this every part was totally new, to the last tyre and hydraulic pump. The wing was of pure delta shape, with CAHI R-II profile of only 3.5 to 3.7 per cent thickness, and with a leading-edge angle of 50° from the root to the inboard engines at 55 per cent semi-span, and 41° 30′ from there to the tip. The tip was cropped to provide mountings for the out­board engines. The leading edge was cam­bered but fixed, while the trailing edge carried rectangular double-slotted flaps and tapered outboard flaperons. At the time this was by far the largest supersonic wing ever flown. Structurally it was based on a
rectangular grid with four transverse spars and seven forged ribs on each side, the skin being formed by forged and machined pan­els. The enormous fuselage was of almost perfect streamline form, which like the wing was skinned with forged and machined pan­els. Only a small two-bay section in the nose formed the pressure cabin for the pilot and navigator seated in tandem downward-eject­ing seats. These were lowered on cables for the crew to be strapped in at ground level, then winching themselves into place. There was neither a fin nor fixed tailplanes. Instead the tail comprised three surfaces, each with a forward-projecting anti-flutter weight and driven by a quadruple power unit in the twin duplex hydraulic systems. A back-up me­chanical control was provided, with rods and levers, but it was expected that this would later be removed. Several possible engines were studied, the finalists being VADo – brynin’s VD-10 and P F Zubts’ 16-17, which was replaced by the 17-18. Construction of the aircraft outpaced both, and in the end the M-50 had to be powered by two Dobrynin VD-7 turbojets on the underwing pylons and two more on the wingtips. As these were tem­porary they were installed in simple nacelles with plain fixed-geometry inlets. Rated at 9,750kg (21,4951b), these were basically the same engines as those of the 3M. Likewise the main landing gears appeared to be simi­lar to those of the previous bomber, but in fact they were totally new. One of the basic design problems was that the weapons bay had to be long enough to carry the llm (36ft) M-61 cruise missile internally. This forced the rear truck, bearing 63 per cent of the weight, to be quite near the tail, reducing the effective mo­ment arm of the tailplanes and threatening to make it impossible for the pilot to rotate the aircraft on take-off. One answer would have been to use enormous tailplanes, greatly in­creasing drag, but a better solution was to do what the OKB had pioneered with the M-4 and 3M and equip the steerable front four – wheel landing gear with a double-extension hydraulic strut. Triggered by the airspeed reaching 300km/h (186mph), this forcibly ro­tated the aircraft 10° nose-up. Another unique feature was that each main gear incorporated a unique steel-shod shoe which, after land­ing, was hydraulically forced down on to the runway, creating a shower of sparks but pro­ducing powerful deceleration, even on snow. For stability on the ground twin-wheel tip pro­tection gears were fitted, retracting forwards immediately inboard of the wingtip engines. All fuel was housed in the fuselage, and yet another unique feature was that to cancel out the powerful change in longitudinal trim caused by the transonic acceleration to su­personic flight fuel was rapidly pumped from Nol tank behind the pressure cabin to No 8 tank in the extreme tail (and pumped back on deceleration to subsonic flight). Over 10 years later the same idea, credited by Myasishchev to L Minkin, was used on Concorde. Flight testing of the M-50 at Zhukovskii was remark­ably rapid, though the aircraft proved stub­bornly subsonic, stopping at Mach 0.99 even in a shallow dive at full power. In early 1960 the M-50 was modified with afterburning VD-7M engines with a maximum rating of 16,000kg (35,275 Ib) on the inboard pylons and derated VD-7B engines rated at 9,500kg (20,944 Ib) on the wingtips. This was consid­ered to offer the best compromise between available thrust, mission radius and propul­sion reliability. The engine installations were redesigned, all four having large secondary cooling airflows served by projecting ram in­lets above the nacelle. The outer engines were mounted on extensions to the wing housing new wingtip landing gears which re­tracted backwards.

The M-52 was under construction from No­vember 1958 and differed in many respects. It was to be powered by four Zubts 17-18 bypass engines each rated at 17,700kg (39,021 Ib). All four were served by efficient variable multi­shock inlets. The inner engines were ‘set at an angle in relation to the chord line’ and the outers were attached to larger pylons with forward sweep. The nose was redesigned and housed navigation/bombing radar, the crew sat side-by-side, a small horizontal sur­face was added on top of the rudder, a re­tractable flight-refuelling probe was added, the interior was rearranged, a remotely con­trolled barbette was fitted in the tail with twin GSh-23 guns, and provision was made to carry one M-61 internally or four Kh-22 cruise missiles scabbed on semi-externally in pairs conforming to the Area Rule. This aircraft was structurally complete in 1960 but when OKB – 23 was closed it was scrapped.

The M-50 was an extraordinary example of an aircraft which physically and financially was on a huge scale yet which had very limit­ed military value. Not least of the remarkable features of this programme was its relative freedom from technical troubles, even though virtually every part was totally new.

Purpose: To transport outsize cargoes. Design Bureau: EMZ (Eksperimental’nyi Mashinostroitel’nyi Zavod, experimental engineering works) named for V M Myasishchev.

After directing CAHI (TsAGI) from 1960, Mya­sishchev returned to OKB No 23 in early 1978 in order to study how a 3M strategic bomber might be modified to convey large space launchers and similar payloads. In particular
an aircraft was needed to transport to the Baikonur launch site four kinds of load: the nose of the Energiya launcher; the second portion of Energiya; the Energiya tank; and the Buran spacecraft, with vertical tail and engines removed. These loads typically weighed 40 tonnes (88,183 Ib) and had a diameter of 8m (26ft). Myasishchev had pre­viously calculated that such loads could be flown mounted above a modified 3M bomber. He died on 14th October 1978, the programme being continued by V Fedotov. While design went ahead, three 3MN-II tanker aircraft were taken to SibNIA (the Siberian State Research Instiutute named for

SAChaplygin) and put through a detailed structural audit preparatory to grafting on a new rear fuselage and tail, and mountings for the external payload. The modified aircraft were designated 3M-T. All were rebuilt with zero-life airframes and new engines, but ini­tially without payload attachments. One was static-tested at CAHI while the other two were completed and flown, tne first on 29th April 1981. After a brief flight-test programme they were equipped to carry pick-a-back pay­loads, and in Myasishchev’s honour redesig­nated VM-T Atlant. The first flight with a payload was made by AKucherenko and crew on 6th January 1982. Subsequently the two Atlant aircraft carried more than 150 pay­loads to Baikonur.

The most obvious modification of these air-

craft was that the rear fuselage was replaced by a new structure 7m (23ft) longer and with an upward tilt, carrying a completely new tail. This comprised modified tailplanes and ele­vators with pronounced dihedral carrying in­ward-sloping fins and rudders of almost perfectly rectangular shape, with increased total area and outside the turbulent wake

flight-control and autopilot system. The for­ward fuselage was furnished with work sta­tions for a crew of six. The aircraft were given civilian paint schemes, one being registered RF-01502 and the other being RF-01402 and fitted with a flight-refuelling probe. To support their missions the PKU-50 loading and un­
loading facility was constructed at spacecraft factories, including NPO Energiya at Moscow Khimki, and at the Baikonur Cosmodrome. These incorporated a giant gantry for careful­ly placing the payloads on the carrier aircraft.

Despite the turbulent aerodynamics down­stream of the external payloads, this dramat­

ic reconstruction proved completely success­ful. In the USA a 747 was used to airlift Shuttle Orbiters, but no other aircraft could have car­ried the sections of Energiya.

Purpose: To fly reconnaissance missions at very high altitude.

Design Bureau: EMZ named for V M Myasishchev.

Though not an experimental aircraft, the M-17 qualifies for this book because of its nature, its ancestry, and the fact that it was the basis for the M-55 research aircraft. The concept of manned reconnaissance aircraft penetrating hostile airspace at extreme altitude was com­
mon in the Second World War, and in the Cold War reached a flash point on 1st May 1960 when the U-2 ofF G Powers, a CIA pilot, was shot down over Sverdlovsk. One of the American alternatives studied and then actu­ally used was unmanned balloons launched in such a way that prevailing winds would carry them across Soviet territory. They could change altitude, and could carry not only re­connaissance systems but also explosive charges. This threat could have been serious,

and the PVO (air defence forces) found it dif­ficult to counter. Though still at CAHI, Mya­sishchev was made head of a secret EMZ tasked with Subject 34, a high-altitude bal­loon destroyer. Called Chaika (Gull) from its inverted-gull wing, it was to be powered by a single Kolesov RD-36-52 turbojet of 12,000kg (26,4551b) thrust. To reduce jetpipe length the tail was carried on twin booms. In the nose was to be radar and the highly pressur­ized cockpit, while between the engine inlet ducts was a remotely controlled turret hous­ing a twin-barrel GSh-23 gun. Secretly built at Kumertau helicopter plant in Bashkirya, the Chaika was first flown in December 1978 by K V Chernobrovkin. He had been engaged in taxi tests, and had not meant to take off but in a snowstorm became airborne to avoid hit­ting the wall of snow on the right side of the runway. In zero visibility he hit a hillside. The programme was relocated at Smolensk, where the second aircraft was constructed to a modified design, designated M-l 7. The first, No 17401, was first flown by E VChePtsov at Zhukovskii on 26th May 1982. It achieved a lift/drag ratio of 30, and between March and May 1990 set 25 international speed/climb/ height records. In 1992 it investigated the ‘hole’ in the ozone layer over the Antarctic. The second M-17, No 17103, was equipped with a different suite of sensors. From the M – 17 was derived the M-55 Geofizka described next.

The M-17 had an all-metal stressed-skin structure designed to the low factor of 2. The remarkable wing had an aerofoil of P-173-9 profile and aspect ratio of 11.9, and on the ground it sagged to an anhedral of-2° 30′. The original wing had 16 sections of Fowler flap and short ailerons at the tips, but it was re­designed to have a kinked trailing edge with simplified flaps and longer-span two-part ailerons. Large areas of wing and tail were skinned with honeycomb panels. Flight con­trols were manually operated, in conjunction with a PK-17 autopilot. The tricycle landing gears retracted hydraulically, the 210kg/cm2 (3,000 lb/in2) system also operating other ser-

vices including three airbrakes above each wing. The engine was an RD-36-51V, with a take-off rating of 12,000kg (26,455 Ib) and nominal thrust of half this value. Cruise thrust at 21,000m (68,898ft) was 600kg (1,32315). T – 8V kerosene was housed in two 2,650 litre main tanks, two 1,550 litre reserve tanks and a 1,600 litre collector tank, a total of 10,000 litres (2,200 Imperial gallons). The pressur­ized and air-conditioned cockpit housed a
very fully equipped K-36L seat, and among other equipment the pilot wore a VKK-6D suit and VK-3M ventilated suit, and a ZSh-3M pro­tective helmet and KM-32 mask overlain by a GSh-6A pressurized helmet. Avionics were extremely comprehensive.

The M-17 fulfilled all its design objectives. The successive changes in both mission and aircraft design were caused solely by political factors.

Purpose: To study the ozone layer and perform many other surveillance tasks. Design Bureau: EMZ named for V M Myasishchev, General Designer V K Novikov.

The M-l 7 proved so successful in its basically politico-military role that it was decided in 1985 to produce a derived aircraft specifically tailored to Earth environmental studies. The first M-55, No 01552, was first flown on 16th August 1988, the pilot being Nil Merited Pilot Eduard V Chel’tsov who had carried out the initial testing ofthe M-1 7. Three further exam­ples were built, Nos 55203/4/5. Further single – seaters, plus the M-55UTS dual trainer, the Geofizka-2 two-seat research aircraft and other derived versions, have been shelved through lack of funds.

Structurally the M-55 was designed to a load factor increased from 2 to 5. This result­ed in a new wing which instead of having left/right panels joined on the centre line has inner and outer panels joined to a centre sec­tion. Aspect ratio is reduced to 10.7, and aero­dynamically the wing retains the P-173-9 profile but has redesigned flaps, ailerons and upper-surface airbrakes. The horizontal tail is modified, with full-span elevator tabs and square tips. The fuel capacity is increased to

10,375 litres (2,282 Imperial gallons), and range/endurance was further increased by changing to a pair of P A Solov’yov D-30-10V turbofans each rated at 9,500kg (20,944 Ib) take-off thrust, and with a combined cruise thrust at 21km (68,898ft) of 670kg (l,4771b). Apart from the landing gear the aircraft was almost totally redesigned, the front of the na­celle being much deeper and more capa­cious, the engine bays being lengthened, and the flight controls being operated by a dual­channel digital system with manual rever­sion. In standard form the M-55 carries a payload of up to 1.5 tonnes (3,307 Ib), typical­ly comprising a Radius scanning radiometer with swath width of 20km (12.4 miles), a
choice ofIR linescanners with swath width of 25km (15.5 miles), an Argos optical scanner with swath width of 28km (17.4 miles), an A-84 optical camera with swath width of 120km (74.6 miles) and a choice of SLARs (sideways-looking airborne radars) with max­imum swath width of 50km (starting at 30km and extending to 80km) on each side. Cover­age of 100,000km2 (38,610 square miles) per hour is matched to an instrumentation trans­mission rate of 16 Mbits per second.

The EMZ have created a versatile research and geophysical aircraft which is being pro­moted for such varied tasks as search/rescue, mapping, ozone studies, hailstorm preven­tion and agricultural monitoring.