Category Soviet x-plenes

Grokhovskii G -31, Y akob Alksnis, Strekoza

Purpose: To build a troop-carrying glider; this was later modified into powered aircraft.

Design Bureau: WS-RKKA (Red Army special design team for aviation forces), director Pavel Ignatyevich Grokhovskii (1899-1946).

Grokhovskii had a brief but intense career, forming a branch of WS-RKKA in Leningrad in 1934 and seeing it liquidated in 1936. Most of his designs were concerned with as­sault by airborne forces, and all showed a re­markable originality. The G-61 was a ‘people pod’ able to house seven armed troops and actually flown attached under each wing of an R-5, a mass-produced 700hp biplane. The G-31 (in some documents called G-63i>/s), named for WS Gen Yakob Alksnis, was a giant cargo glider, designed by Grokhovskii and B D Urlapov to carry troops lying inside the wing. From this Grokhovskii produced the G-31 powered aircraft. First flown in late 1935, it flew to Moscow in 1936 for RKKA test­ing. It was eventually decided that the
arrangement of troops packed inside the wing, with no chance of escape in flight, was unacceptable. In any case, the concept of a powered glider for assault operations was eventually considered unsound.

Sharing a strengthened version of almost the same airframe as the glider, the G-31 (again named for Alksnis and also dubbed Strekoza, dragonfly) was a graceful aircraft as befits a powered version of a glider. Though intended for military purposes it was one of several types designed in the 1930s with no consideration of speed, because this was not thought significant. The airframe was wooden, with a vestigial fuselage of multiply veneer formed by presses with double curva­ture. On the front was a puny 100hp M-l 1 five – cylinder radial. Subsequently Grokhovskii built a G-31 with a strengthened structure matched to the 700hp M-25, an imported (later licensed) Wright R-1820 Cyclone. This was fitted in a Townend-ring cowl and it drove a Hamilton light-alloy ground-ad­justable propeller. It is believed that later a three-blade flight-variable Hamilton Standard
was fitted. As in the glider there were cockpits for a pilot and flight engineer, while between the wing ribs were compartments for 18 troops, nine in each wing (drawings show eight in each wing). They boarded and were extracted through hinged leading edges, which were transparent, as in the G-61 pods.

Few details of the G-31 have survived. Clearly the naming of this aircraft and its predecessor after Alksnis was a mistake, because he was arrested in 1936 and execut­ed in 1938. The close-knit Grokhovskii team was ‘liquidated’ very soon after the General’s arrest.

Grokhovskii G -31, Y akob Alksnis, Strekoza

Dimensions (M-25 engine)

Span

Length

Wing area

28.0m

13.9m

70.5m2

91 ft M in 45 ft 7n in 759 11!

Weights

Empty

1,400kg

3,086 Ib

Loaded

3,200kg

7,055 Ib

Performance Maximum and cruising speed limited to

135km/h

84 mph

No other data.

 

Left: G-31 with M-25 engine.

Below left: G-31 glider.

 

Below right: G-31 with M-l 1 engine.

Grokhovskii G -31, Y akob Alksnis, Strekoza

 

Grokhovskii G -31, Y akob Alksnis, Strekoza

Grokhovskii G -31, Y akob Alksnis, Strekoza

Lavochkin La 7R and f120Rf

Purpose: To use a rocket engine to boost a fighter’s flight performance.

Design Bureau: OKB of Semyon A Lavochkin.

By early 1944 the all-wood La-5 fighter had given way in production to the La-7, with metal spars and other modifications. The en­gine remained the ASh-82FN 14-cylinder radi­al rated at 1,600hp. One ofthe first production aircraft was fitted with an RD-1 rocket engine in order to boost its performance, especially at extreme altitudes where the ASh-82 family of engines were less impressive. The installa­tion was completed in the late autumn of 1944, and ground testing occupied nine weeks. In the last week of the year the as­signed pilot, Georgii M Shiyanov, began the flight-test programme. Together with AVDavydov the La-7R was flown 15 times without serious malfunction, though the pro-

Lavochkin La 7R and f120Rf

Above: Ground test of ‘120R’ rocket engine. Opposite: Two views of La-7R.

gramme had to be abandoned because of progressive weakening of the rear fuselage by vapour and accidental spillage of the acid. Testing was continued with the RD-lKhZ in­stalled in a second La-7R in early 1945. Brief testing was also carried out with a similar en­gine installed in the ‘120R’. On 18th August 1946 this aircraft excited spectators at the Avi­ation Day at Tushino by making a low flypast with the rocket in operation.

Both the La-7R test aircraft were originally standard production fighters. The RD-1 was one of the world’s first liquid-propellant rock­et engines to fly in a manned aircraft, the de­signer being V P Glushko. The thrust chamber was mounted on a framework of welded steel tubes carried behind a modified rear fuselage frame, which merged at the top into the fin trailing edge. To accommodate the rocket the lower part of the rudder was re­moved. In the fuselage behind the cockpit were a stainless-steel tank for 180 litres (39.6 Imperial gallons) of RFNA (concentrated red fuming nitric acid) and 90 litres (19.8 Imperi­al gallons) of kerosene. These propellants were supplied by a turbopump energised by hot gas bled from the main thrust chamber. The turbine had a governed speed of 26,000rpm, and drove pumps for the two pro­pellants plus lubricating oil and water sup­plied from a small tank to cool the turbine and thrust chamber walls. Mass of the installation was approximately 100kg (220 Ib), or 215kg (474 Ib) complete with propellants and water. The basic RD-1 had electrical ignition, while the RD-1KhZ had automatic chemical ignition from hypergolic liquids. The rocket was ofthe on/off type, cut in or out by a switch on the main throttle lever. It could not be varied in thrust (300kg, 661 Ib, at sea level), but could be shut off before the tanks were empty, nor­
mal duration being 3 to 31/2min. Both La-7R air­craft retained their armament of two UB-20 cannon. The ’ 120R’ differed in having an ASh – 83 engine, rated at 1,900hp, armament of two NS-23 guns and in other details.

Together with such other aircraft as the Pe – 2RD and Yak-3RD these test-beds confirmed the value of a rocket engine in boosting per­formance at high altitude. On the other hand they also confirmed that RFNA is not compat­ible with a wooden structure, and in any case the value of three minutes of boost was con­sidered questionable.

Dimensions (both)

Span

Length

Wing area

9.8m

8.6m

17.59m2

32 ft IK in 28 ft TM 189ft2

Weights (La-7R)

Empty

2,703kg.

5,959 Ib

Fuel and propellants

604kg

l,3321b

Loaded

3,500kg

7,716 Ib

Weights (‘120R’)

Empty

2,770kg

6,107 Ib

Fuel and propellants

470kg

l,0361b

Loaded

3,470kg

7,650 Ib

A standard La-7 typically had empty and loaded weights of 2,600kg and 3,260 kg

Performance

(La-7R) generally unchanged, but maximum speed at 6 km (19,685 ft) altitude was increased from 680 km/h (422.5 mph) to 752 km/h (467 mph).

Service ceiling was increased from 10,700 m (35,105 ft) to 13,000 m (42,651 ft).

The only figure recorded for the ‘120R’ is a speed (height unstated) of 725 km/h (450.5 mph), but this speed (at 7,400 m) is also recorded for the unboosted ‘120’.

Lavochkin La 7R and f120Rf

Lavochkin La 7R and f120RfLavochkin La 7R and f120Rf

Ye-6T/l (Ye-66A)

In 1960 the Ye-6T/l, the first true series-built MiG-21, callsign Red-31, was rebuilt for record purposes, with various modifications. In order not to reveal too much to the FAI in­ternational body, it was given the invented designation Ye-66A. The most obvious change was to attach a rocket package un­derneath the fuselage. The rocket engine was designated S-3/20M5A, the ultimate version of Dushkin’s family burning kerosene and RFNA fed by peroxide turbopumps. The propellants were packaged with the engine and control system in a large gondola designated U-21. Thrust was 3,000kg (6,614 Ib) at sea level, ris­ing to about 3,700kg (8,150 Ib) at high altitude. The rocket nozzle was angled 8° downwards, but despite this it was necessary to replace the usual MiG-21 underfin by two shorter but deeper ventral fins each inclined outwards. The main engine was replaced by an R-l 1F2- 300, with a maximum afterburning rating of 6,120kg (13,492 Ib); this engine later became standard on the MiG-21 PF. Other modifica­tions included 170 litres (37.4 Imperial gal­lons) of extra kerosene fuel in a spine fairing behind the canopy, and a fin extended for­wards to increase area of the vertical tail to 4.44m2 (47.7ft2). The Ye-66A did not set any ratified speed records, but on 28th April 1961 it was flown by G K Mosolov in a zoom to a new world absolute height record of 34,714m (113,891ft). He made a low flypast with rock­et in operation at the airshow at Moscow Tushino on Aviation Day (9th July) 1961.

Petlyakov Pe-2 experimental versions

Purpose: To test various items on modified Pe-2 aircraft.

Design Bureau: Basic aircraft, ‘100’ in special prison CCB-29 (TsKB-29), later V M Petlyakov’s own OKB.

Production of this outstanding fast tactical bomber totalled 11,427. One of the experi­mental wartime versions was the Pe-2Sh (Shturmovik, assaulter) with various combi­nations of20mm ShVAK cannon and 7.62mm ShKAS either firing ahead from a gondola or installed in one or more batteries firing obliquely down from what had been the fuse­lage bomb bay. The Pe-2VI and Pe-2VB were
special high-altitude versions with pressur­ized cabins and VK-105PD engines with two – stage superchargers. The Pe-2RD was fitted with a Dushkin/Glushko RD-1 or RD-lKhZ rocket engine installed in the tailcone, with the tanks and control system in the rear fuse­lage. This aircraft was tested in 1943 by Mark L Gallai. Like the similarly modified Tu-2, the Pe-2 Paravan (paravane) had a 5m (16ft Sin) beam projecting ahead of the nose from the tip of which strong cables led tightly back to the wingtips. While the Tu-2 had a tubular beam, that of the Pe-2 was a truss girder, and the balloon cables struck by the wires were deflected further by large wingtip rails. From
1945 one Pe-2, as well as at least one Tu-2, was used by CIAM and Factory No 51 to flight test a succession of pulsejet engines begin­ning with captured German Argus 109-014 flying-bomb units. Test engines were mount­ed above the rear fuselage, with fuel fed by pressurizing the special aircraft tank to 1.5kg/cm2 (21.31b/in2). In 1946-51, under V N Chelomey, Factory 51 improved this Ger­man pulsejet into a succession of engines designated from D-3 to D-14-4. All the early models were tested on the Pe-2, despite fatigue caused by the severe vibration.

Petlyakov Pe-2 experimental versions

Petlyakov Pe-2 experimental versions

Rear defence by aft-firing RO-82 rockets: RUB-2L dorsal and RUB-4 ventral.

 

Petlyakov Pe-2 experimental versionsTop left: Twin ShVAK-20 cannon in Pe-2Sh (two more were further back).

Подпись:
Right: Pe-2VI.

. Sukhoi 100LDU

Purpose: To flight-test canard surfaces. Design Bureau: P O Sukhoi, Moscow

As explained in the history of the T-4, this enormous project required back-up research right across Soviet industry. The Sukhoi OKB
itself took on the task of investigating the proposed canard surfaces. As the only vehicle immediately available was a two-seat Su-7U, with a maximum Mach number of 2 instead of 3, the resulting aircraft – with designation 100LDU – ceased to be directly relevant to the

T-4 and became instead a general canard research vehicle. It was assigned to LIl-MAP test pilot (and future Cosmonaut) Igor Volk, and was tested in 1968-71.

The basic Su-7U, powered by an AL-7FI – 200 with a maximum afterburning rating of 10,100kg (22,282 Ib), was subjected to minor modifications to the rudder and braking- parachute installation, and was fitted with fully powered canard surfaces on each side of the nose. These were of cropped delta shape, with a greater span and area than those of contemporary experimental MiG aircraft, and with anti-flutter rods which were longer and nearer to the tips.

This aircraft fulfilled all test objectives, though the numerical data were of only marginal assistance to the T-4/100 design team.

SLIKHOI 02-10, OR L02-10

. Sukhoi 100LDU

Purpose: To investigate direct side-force control.

Design Bureau: P O Sukhoi, Moscow.

In 1969 this Su-9 was modified for the LII, which wished to investigate the application of direct side force. The LII had been concerned at American research into direct lateral or ver­tical force which could enable a fighter to rise, fall, move left or move right without changing the aircraft’s attitude. In other words such an aircraft could keep pointing at a target in front while it crabbed sideways (for example). Testing began in 1972. In 1977 the aircraft was returned to a Sukhoi OKB factory and had the upper nose fin removed, testing continuing as a joint LII/Su programme. It was further modified in 1979.

Originally this aircraft was a production Su – 9 interceptor, though it never saw active ser­vice. In its first 02-10 form is had substantial vertical fins added above and below the nose. Each fin was pivoted at mid-chord and fully
powered. The pilot was able to cut the nose fins out of his flight-control circuit, leaving them fixed at zero incidence. When they were activated, movement of his pedals drove the fins in unison with each other and in unison with the rudder. The two canard fins moved parallel to the rudder, to cause the aircraft to crab sideways. Each surface was of cropped delta shape, with a lower aspect ratio than the horizontal canards of the S-22PDS. Compared with the lower fin the upper surface had significantly greater height, and it was mounted slightly further forward. Each was fitted with an anti-flutter rod mass,
which during the course of the programme was moved from 40 per cent offin height (dis­tance from root to tip) to 70 per cent. After the 02-10’s first series of tests the upper nose fin was removed (leaving its mounting spigot still in place). Later a cine camera was installed on the fin to record lateral tracking across the ground, and in some of the later tests the wings were fitted with smoke nozzles along the leading edge, to produce visible stream­lines photographed by a camera in a box im­mediately ahead of the radio antenna.

This aircraft generated useful information, but the idea has never been put into practice.

Three different versions of L02-10 test-bed.

. Sukhoi 100LDU

 

Type 346

Type 346Подпись: 346A carried by B-29, front and plan views of any version except 346-3.Подпись: 346A (346D similar)Type 346Подпись: Inboard profile of 346-3Type 346

Purpose: To continue German development of a supersonic rocket aircraft.

Design Bureau: OKB-2 at Podberez’ye, lead designer Hans Rosing, in October 1948 replaced by S M Alekseyev.

On 22nd October 1946 a second group of German design engineers was formed at Pod – berez’ye to continue development of the DFS – 346 supersonic research aircraft originally designed at the DPS (German institute for glid­ing) at Griesheim near Darmstadt. Models, some made in Germany, were tested in CAHI (TsAGI) tunnels, and a North American B-25 was fitted with a mock-up nose to test the cockpit jettison system. In 1947 (date not dis­covered) the 346P (P from planer, glider) un­powered version was taken to the test airfield at Tyoplyi Stan and dropped from under the starboard wing of a captured B-29 (previously USAAF 42-6256). Amazingly, the 346P was flown not by a Russian but by Wolfgang Ziese, who had previously been chief test pilot of the Ger­man Siebel Flugzeugwerke. He had no prob­lems, and brought the glider to a normal landing. In 1948 (date not discovered) the 346­1 high-speed glider version, also known as the 346A, was released from a Tu-4 (B-29 copy) and similarly flown by Ziese to a normal landing. On 30th September 1949 the 346-2, also known as the 346D, was dropped from the B-29 and flown as a glider by Ziese even though it was fitted with rocket propulsion. No propellant was loaded, so the aircraft was much lighter than it would have been with full tanks. Despite this Ziese landed too fast and, more seriously, the landing skid failed to extend, resulting in seri­ous damage to both the aircraft and pilot. This aircraft was repaired, and in October 1950 LII pilot P I Kasmin flew it at Lukhovitsy, according to the record making a normal take-off from the runway despite having only skid landing gear. Ziese recovered, and on 13th August 1951 he flew the final aircraft of this programme, the 346-3, and fired the engines. He flew again on 2nd September, but on the third flight, on 14th September, he lost control. He managed to sep­arate the jettisonable nose from the tumbling aircraft, but this ended the programme. Later versions were abandoned. Various 346 parts were donated to the Moscow Aviation Institute.

Like its American counterpart the Bell XS-1, the 346 was an almost perfectly streamlined body with mid-mounted wings. Unlike the XS – 1, it had a prone pilot position, skid landing gear, swept wings and an extremely squat ver­tical tail with the tailplane on top. Construction was almost wholly flush-riveted light alloy. The wings had NACA-012 profile (12 per cent thick) and a sweep angle of 45° at the /4-chord line. Each wing had two shallow fences from the

Подпись: Opposite page, top: B-25 with 346 cockpit capsule. Подпись:Подпись: Above: 346-2 (346D) nose open showing pilot couch. Right: Looking down into open nose. Below: Three views of 346-2 on B-29. Type 346Подпись: Performance Max speed, intended 2,127 km/h 1,322 mph (Mach 2) in a 2 min full-power burn at high altitude No other data. Type 346leading edge to the plain flap. At the tips were inverse-tapered two-section ailerons, the inner sections being locked at high airspeeds. The elevators were similar in principle. On the 346P the tailplane, with!4-chord sweep of 35°, was fixed and surmounted by a small fixed fin. On the 346-2 and -3 the tailplane was driven by an irreversible power unit over the range -2° 407+2°. The fuselage was of circular sec­tion, with the entire nose arranged to slide forward for pilot entry and to jettison in emer­gency. The pilot lay on his stomach looking ahead through the Plexiglas nosecap, through which protruded the long instrumentation boom. Bottled gas pressure operated the flaps and retracted the skid into a ventral recess which, except for the 346P, could be faired over with twin doors. Under the tail was a small steel bumper. Unlike its predecessors, the 346-3 could be fitted with a curved skid with a levered shock strut hinged under each outer wing. These were jettisoned after take-off. The propulsion system was the Walter HWK 109- 509C, called ZhRD-109-510 in the USSR. This had two superimposed thrust chambers, one which fired continuously whenever the system was in operation, and a larger chamber used only for take-off or for brief periods when max­imum thrust was needed. The cruise chamber was rated at sea level at 300kg (661 Ib), and the main chamber at 1,700kg (3,7481b). The com­bined thrust at high altitude was about 2,250kg (4,960 Ib). Immediately behind the jettisonable nose section was a tank of concentrated hyd­rogen peroxide (called T-Stoff in Germany) while in the centre fuselage were intercon­nected tanks of methanol/hydrazine hydrate (C-Stoff). German turbopumps running on cal­cium permanganate fed the highly reactive flu­ids to the thrust chambers, where ignition was hypergolic (instantaneous).

Probably as much effort went into the 346 programme as the Americans expended on the XS-1 or D-558-II, but there was no comparison in what the programmes achieved. There is no obvious reason why these challenging aircraft, designed for Mach 2, should simply have been abandoned without even reaching Mach 1.

Dimensions

Span 9 m 29 ft 6% in

Length

(346-3, nose to engine nozzles) 13.447 m 44 ft IK in (instrument boom to tailplanes) 15.987 m 52 ft 3SA in Wing area (net) 14.87nf 160ft2

Weights (346-3)

Empty 3,180kg 7,01 lib

Propellants 1,900kg 4,1891b

Loaded 5,230kg ll,5301b

Soviet x-plenes

Introduction

F

or over 70 years from 1918 the world’s largest country was tightly controlled by a tiny group of elderly men in The Kremlin, in Moscow. Their power was absolute. They could take giant decisions, and so could make giant mistakes. They also sometimes found they had to choose between diametri­cally opposed objectives. While on the one hand aviation was a marvellous instrument for propaganda, trumpeting the achieve­ments of the Soviet Union, the underlying theme of Soviet society was of rigid secrecy.

Thus, when The Great Patriotic War began on 22nd June 1941 the outside world knew very little about Soviet aircraft. The knowledge was confined largely to the mass-produced Polikarpov biplane fighters and Tupolev monoplane bombers, and to the ANT-25 monoplane designed to break world distance records. Only very gradually did it become apparent that the austere and sombre Land of the Soviets (this was the name of a record­breaking bomber) was home to an incredible diversity of aircraft.

Other countries – the USA, France, Britain, Italy and increasingly Germany – had numer­ous aircraft companies from which flowed many hundreds of different types of aircraft. They also had individuals who sometimes managed to create aircraft and even form tiny companies, but the aircraft were invariably conventional lightplanes aimed at the private owner. Few people in what became called The West’ would have dreamed that in Stal­in’s realm individuals could even set their sights on high-powered fast aircraft bristling with strange ideas.

At the same time, the Soviet Union was far from being the earthly paradise that was orig­inally intended. It is said that power corrupts, and the record shows that anyone who ‘stuck his head above the parapet’ was likely to get it cut off. It seems incredible that in 1936-40 Stalin should have been able to unleash what was called The Terror, in which anyone who might have posed the slightest threat – for ex­ample, any senior officer in any of the armed forces – was simply put through a show trial on invented charges and shot.

In the aircraft industry, time after time peo­ple who made mistakes, or in some way fell foul of someone more senior, were simply dismissed or even imprisoned (and in a few cases, executed). It is beyond question that this omnipresent air of repression did much to counter the natural enthusiasm of count­less workers who longed for their country to be the greatest on Earth, and a leader in ad­vanced technology. When one reads what happened it seems remarkable that so many diverse aircraft actually got built.

This book is the most comprehensive at­tempt yet to collect the stories of the more important of these X-Planes (experimental aircraft) into one volume. Of course, some of the strange flying machines featured were built after the collapse of the Soviet Union, but we did not want a ponderous title. Translation of the Communist state into an intensely capitalist one has tended to concentrate the mind wonderfully. Whereas 60 years ago Soviet designers could obtain funds for often bizarre ideas which a hard-nosed financial director would have considered an almost
certain non-starter, today Ivan at his modern keyboard and screen knows that if he gets it wrong his shaky firm will go out of business.

Ironically, instead ofbeing a closely guard­ed secret, the experimental aircraft and pro­jects of the Soviet Union are today better documented than those of many Western companies. The process of rationalization has seen almost all the famous names of the aircraft industries of the UK, USA and France disappear. In many cases, and especially in the UK, their irreplaceable archives have been wantonly destroyed, as being of no in­terest to current business. We may never know what strange things their designers drew on paper but never saw built. In con­trast, the Soviet Union never destroyed any­thing, unless there was a political reason for doing so. Accordingly, though this book con­centrates on hardware, it also includes many projects which were built but never flew, and even a few which never got off the proverbial drawing board.

As in several previous books, Yefim Gordon provided much information and most of the illustrations while Bill Gunston wrote the text and put the package together. The in-flight photograph of the MiG 1.44 featured on the jacket is from a Mikoyan video. A special vote of thanks is due to Nigel Eastaway and the Russian Aviation Research Trust who provid­ed the remainder of the visual images.

Sukhoi S-37 experimental fighter.

Soviet x-plenes

 

BICh-17

Purpose: Single-seat fighter.

Design bureau: USP (Control of Special Work) organised by I B Kurchevskii, to which Cheranovskii was invited.

Kurchevskii was the designer of a family of APK and DRP recoilless guns of large calibre (45, 76.2, 80 and 100mm). These operated by firing a projectile down the barrel and a near­ly equal mass plus gun gas from a rear nozzle. Fighters fitted with such guns included the

Grigorovich I-Z and Tupolev ANT-29 and ANT – 46. Cheranovskii completed the design of the BICh-17 in 1935, but in February 1936 Kurchevskii was arrested and his design bu­reau ‘liquidated’. By this time the BICh-17 was ’60 per cent complete’.

BICh-17

 

BICh-17

Подпись: ModelofBICh-17. BICh-17No detailed documentation on this fighter survives, but the drawing shows that it was a typical Cheranovskii ‘parabola’ design. The structure was wood, with skins of birch shpon (multi-ply veneer), the wing having detachable outer panels. The engine was a 480hp M-22 (imported or licence-made Bristol Jupiter) driving a two-blade propeller. The main landing gears retracted, probably inwards, and the elevators were divided into inner and outer sections by the two 80mm APK guns. The pilot sat under a typical Cheranovskii upward-hinged canopy which formed the front part of the fin. Aircraft left incomplete.

Grokhovskii G-37, ULK

Purpose: ‘Universal flying wing’.

Design Bureau: WS-RKKA Leningrad, Chief Designer Vladimir Rentel.

The numbering of’Grokhovskii’ aircraft is dif­ficult to interpret, and this aircraft preceded the G-31. The concept was that of a versatile aircraft for airborne assault, but it was soon evident that a Universalnoye Letayushchyeye Krylo, universal flying wing, would have wide commercial appeal. Construction was as­signed to Vladimir Rentel, who had the air­craft built in Grebno (rowing) port, Leningrad. It was taken to the airfield where from No­vember 1935 it was tested by VPChkalov, who was impressed. He later flew it to Moscow in 2hrs SOmin (average 250km/h, 155mph, which Shavrov says was ‘almost a record’). The G-37 was used for a long series of tests, including dropping of heavy loads.

The G-37 was a remarkably capable early example of an aeroplane designed to lift a de­tachable payload container (later types in­
cluded the Fi333, Miles M.68 and Fairchild XC-120). To save time the wing was that of an ANT-9 (PS-9), made of Kolchug duralumin with mainly corrugated dural skin, though the ailerons did not project beyond the wing tips. It is possible this wing came from a crashed PS-9 along with the 680hp BMW VI water – cooled V-12 engines, though these were in a different installation. The engine cowls were extended down into large trousers over the main landing gears, which contained the en­gine-cooling radiators. At the rear they extend­ed into tail booms, all these structures being of light alloy. Each boom had a tailwheel, and the twin-finned tail was duralumin with fabric cov­ering. On the centreline the wing was expand­ed into a small nacelle for the pilot and engineer. The underside of the centre wing was provided with attachments for a standard pre-loaded payload container, though no pho­tographs have been found with this in place. The completed G-37 was painted with gay stripes and stylized red stars and slogans.

There seems little doubt that this was an excellent and potentially versatile aircraft, and it is not known why it was never ordered for military or civil use.

Dimensions

Span

22.5m

73ft93/4in

(possibly for a develops:d version,

Shavrov cites)

23.7m

77 ft 9/4 ill

Length

13.85m

45 ft 5% in

(Shavrov)

16.0m

52 ft 6 in

Wing area

84.0m2

904 ft2

Weights

Empty

3,100kg

6,834 Ib

Loaded

5,700kg

12,566 Ib

Performance

Max speed at sea level

235km/h

146 mph

at 2,500m (8,200ft)

285 km/h

177 mph

Cruising speed at

2,500m (8,200 ft)

250 km/h

155 mph

Time to climb to 6 km

16min

(19,685ft)

Service ceiling

6,500 m

21,325ft

Landing speed

90 km/h

56 mph

Grokhovskii G-37, ULK

Three views of G-37 without payload container.

 

Grokhovskii G-37, ULKGrokhovskii G-37, ULK

Lavochkin ’164’ (La-126PVRD) and ’138’ (130PVRD-430)

Purpose: To test the use of ramjets to boost propulsion of a fighter.

Design Bureau: The OKB of S A Lavochkin.

By 1942 M M Bondaryuk had achieved reli­able operation with the VRD-430. By this time this refined subsonic ramjet had flown over 200 times on test-bed aircraft. In early 1946 two were attached under the wings of’ 126′, a slightly modified La-7, to produce the La – 126PVRD, given the OKB number ‘164’. The assigned pilot was A V Davidov, and he tested this aircraft between June and September 1946.

The VRD-430 was a simple ramjet designed for subsonic operation. It was made mainly of steel, and had a diameter of400mm (1ft 3%in).

Able to burn almost any thin hydrocarbon fuel, including high-octane petrol (gasoline), it had a thrust in the region of 300kg (661 Ib), but performance data for this engine have not been found, neither have details of its fuel and control system. The La-126 was based on the La-7 but had a completely metal stressed – skin airframe, a new wing of so-called lami­nar profile, a modified canopy and many other changes, including the devastating ar­mament of four NS-23 guns firing projectiles with more than twice the mass of the 20mm ShVAK. The La-138 was basically an La-9 fighter, in which the new wing and armament of the La-126 were matched with a com­pletely redesigned fuselage. As before, a VRD-430 ramjet was hung under each wing,
to produce the ‘164’. The ‘138’ was the desig­nation of the ‘130’ after it had been fitted with two VRD-430 ramjets. It emerged in this form at the end of 1946, and flight tested 20 times between March and August 1947. Very few details survive regarding this aircraft, possibly because in the turbojet era it did not appear to be important.

The VRD-430 demonstrated its ability to boost speed (see below) but at the expense of high fuel consumption and a serious in­crease in drag when the ramjets were not being used. It is not clear why the La – 126PVRD speed was ‘boosted by 64km/h’ by the ramjets, while the corresponding figure for the La-138 was almost twice as great.

LAVOCHKIN ‘164’ (La-126PVRD AND ‘138’ (130PVRD-430)

Подпись: La-126PVRD, also called La-7/2PVRD-430 or La-164.Lavochkin ’164’ (La-126PVRD) and ’138’ (130PVRD-430)Подпись: Dimensions (164) Span Length Wing area

Подпись: La-138, also called La-130/2PVRD-430.
Lavochkin ’164’ (La-126PVRD) and ’138’ (130PVRD-430)

9.8m 32 ft 1% in

8.64m 28 ft 41i in

17.59m2 189.3ft2

Weights

Empty 2,710kg 5,974lb

Loaded 3,275kg 7,22011)

Performance

Max speed at 2,340 m (7,678 ft) 694 km/h 431 mph Range with brief VRD usage 730 km 454 miles

Landing speed 145.6 km/h 90.5 mph

/run 688 m 2,257 ft

Dimensions (138) Span

9.8m

32 ft % in

Length

8.625 m

28 ft 3n in

Wing area

17.59nf

189.3ft2

Weights

Empty

3,104kg

6,843 Ib

Loaded

3,730kg

8,223 Ib

Performance

Max speed at 6,000 m (19,685 ft) 760 km/h

472 mph

which does not quite equate with the contemporary claim of

‘boosted by 107-1 12 km/h’ Range with brief VRD usage

1,100km

683.5 miles

Take-off run

450m

1,476ft

Landing speed

139 km/h

86.4 mph

Lavochkin ’164’ (La-126PVRD) and ’138’ (130PVRD-430)

MAI EMAI-1