Tupolev SB

Tupolev SB (SB-2) Soviet 1930s twin-engine fast bomber, preserved 2M-100A airframe with red-star markings
Aircraft Museum / Bombers / Tupolev SB

Tupolev SB
The fast bomber that briefly outran the fighters

A Soviet all-metal monoplane so quick that, when it appeared in 1934, most fighters in the world could not catch it — and so lightly defended that, seven years later, it was slaughtered wholesale.

~450 km/hTop speed (M-103, est.)
1934First flight
3Crew
~6,600+Built (most-produced 1930s bomber)
Preserved Tupolev SB 2M-100A. Photo: Alan Wilson, CC BY-SA 2.0, via Wikimedia Commons
Role Fast medium bomberEra 1934–1945Engine 2 × Klimov M-100 / M-103 V12Origin Soviet UnionStatus Retired · rare survivorsCan I fly a Tupolev SB?
The Story

The Tupolev SB: the Soviet bomber that briefly flew faster than the fighters chasing it

In the early 1930s the Soviet Union set out to build a skorostnoi bombardirovshchik — a “fast bomber” that would rely on sheer speed rather than guns or armour to survive. The result, designed by Andrei Tupolev’s bureau under the day-to-day leadership of Alexander Arkhangelsky and flown as the prototype ANT-40 in 1934, was one of the most advanced combat aircraft of its moment: a clean, all-metal, stressed-skin twin-engine monoplane at a time when much of the world still flew fabric-covered biplane bombers.

When the type entered service around 1936 as the SB (often written SB-2), it genuinely lived up to its name. With a top speed commonly cited at around 450 km/h, the SB could outrun most contemporary fighters in level flight. That advantage was showcased almost immediately in Spain, where Republican SBs — nicknamed the “Katiuska” — ranged over Nationalist territory with near impunity, until the arrival of the Messerschmitt Bf 109 abruptly ended the era of the untouchable bomber.

Through the late 1930s the SB was everywhere the Soviet Union projected air power. It fought in China against Japan, flown both by Soviet “volunteer” crews and the Chinese Air Force; it bombed Japanese forces at Khalkhin Gol in 1939; and it raided Finland during the Winter War, where Finnish fighters and flak began to take a heavy toll. Built in enormous numbers — usually estimated at more than 6,600 airframes, which makes it very likely the most-produced bomber of the 1930s — it was also licence-built in Czechoslovakia as the Avia B-71.

But an aircraft designed for speed in 1934 could not stay ahead of fighter development forever. By the time Germany launched Operation Barbarossa in June 1941, the SB was obsolete: too slow, too lightly armed, and too flammable. Sent out in daylight, often without fighter escort, SB regiments were cut to pieces by the Luftwaffe in the opening weeks of the invasion. Survivors were pushed into night operations and training roles, and the type faded from front-line service as newer bombers such as the Pe-2 took over. Its story is a compact parable of interwar aviation: the price of standing still while the technology race accelerates.

When it first flew in 1934 the SB was faster than almost any fighter alive. Five years later the same airframe had become a death-trap — the whole arc of interwar air power in a single design.
01The Tupolev SB’s names explained: ANT-40, SB, SB-2 and “Katiuska”

The aircraft carried several designations across its life. ANT-40 was the Tupolev design-bureau prototype designation (ANT for Andrei Nikolaevich Tupolev). In service it became the SB — from the Russian Skorostnoi Bombardirovshchik, “fast bomber” — and is widely referred to as the SB-2 in Western sources, with sub-variants such as the SB-2M-100, SB-2M-103 and the improved SB-bis. In Republican Spain it earned the nickname “Katiuska” (after a popular operetta of the day). Civil and transport conversions were designated PS-40 and PS-41. Designations and exact figures vary between sources, so treat sub-type numbers as approximate.

02Why the Tupolev SB mattered: an all-metal fast bomber ahead of its time

The SB was influential out of proportion to how it is remembered today. Its combination of monoplane layout, retractable undercarriage, all-metal construction and high speed pointed directly at the shape of the medium bombers that would fight the Second World War. It gave the Soviet Union a modern strike aircraft years before many rivals, and its performance in Spain forced fighter designers everywhere to take the “fast bomber” threat seriously. That the SB was then overtaken so completely by 1941 does not diminish how genuinely advanced it had been in 1934 — it simply shows how fast the pace of aviation was in that decade.

Design & Engineering

How the Tupolev SB was built for speed

01

A clean all-metal monoplane built around speed

The SB was an all-metal, stressed-skin cantilever monoplane with a retractable undercarriage and a slim, aerodynamically clean fuselage — a generation ahead of the fabric biplane bombers it replaced. Speed, not protection, was the whole design philosophy.

02

Twin Klimov V12s, born from Hispano-Suiza

Power came from two Klimov M-100 and later M-103 liquid-cooled V12s — Soviet-built derivatives of the French Hispano-Suiza 12Y. The M-103 gave roughly 960 hp each, enough to push the light airframe to around 450 km/h.

03

Light guns, light bombs: the speed gamble

Defence was minimal: typically four 7.62 mm ShKAS machine guns and an internal bomb load of only around 600 kg. The bet was that no fighter could catch it — a bet that paid off in 1936 and failed catastrophically by 1941.

03The Tupolev SB’s engines: Klimov M-100 and M-103 explained

The SB’s engines trace directly to the Hispano-Suiza 12Y, licence-produced in the USSR by the Klimov works. Early aircraft used the M-100 (about 750–860 hp); later production switched to the more powerful M-103 (commonly cited around 960 hp), giving the definitive SB-2M-103 / SB-bis its best performance. The water-cooled V12s were relatively light and streamlined, which suited the fast-bomber concept, but their radiators and coolant lines were vulnerable to battle damage — a weakness that told heavily once fighters could catch the SB. Power figures vary by source and variant; treat them as approximate.

04The Tupolev SB’s fatal flaw: defensive weakness and vulnerability

Because the design assumed speed would keep it safe, the SB carried only a handful of rifle-calibre machine guns, no meaningful armour for the crew, and unprotected fuel tanks. When it could no longer outrun its attackers — against the Bf 109 in Spain, Finnish fighters in the Winter War, and the Luftwaffe in 1941 — those economies became lethal. Unescorted daylight formations were especially exposed, and losses in the opening phase of Barbarossa were among the heaviest suffered by any bomber type of the early war. The SB is often cited as a textbook example of how quickly an “untouchable” aircraft can become obsolete.

Technical Data

Tupolev SB specifications

Baseline note: the figures below describe the SB 2M-100A, the version produced from late 1936 and the one that went to Spain and China — the aeroplane that caused the shock, rather than the later machine that absorbed the punishment. Deltas for the M-103-engined SB bis family and the Czech-built Avia B-71 are in grey. Note that the widely reproduced Wikipedia data table describes the SB 2M-103, not this aircraft.

Dimensions & weights

Crew
3 (pilot; navigator-bombardier who also worked the nose guns; radio operator who worked both the dorsal and the ventral gun)
Length
12.27 m (40 ft 3 in) — SB 2M-103 12.57 m (41 ft 3 in)
Wingspan
20.33 m (66 ft 8 in); the ANT-40 RTs prototype had a shorter 19.00 m (62 ft 4 in) wing
Height
3.60 m (11 ft 10 in); Czech and Russian tables commonly give 4.24 m (13 ft 11 in), a different datum rather than a different aeroplane
Wing area
56.7 m2 (610.3 sq ft) — the broad high-aspect-ratio wing that gave the type its altitude performance and its nickname
Wing loading
101 kg/m2 (20.7 lb/sq ft) at normal loaded weight
Empty weight
4,138 kg (9,123 lb) — SB 2M-103 4,768 kg (10,511 lb)
Normal loaded weight
5,732 kg (12,637 lb) — SB 2M-103 6,308 kg (13,907 lb)
Maximum take-off weight
6,462 kg (14,246 lb) — SB 2M-103 7,880 kg (17,372 lb)
Internal fuel
About 1,520 litres (334 imp gal / 402 US gal); the 2M-103 tenth series added provision for two 368-litre (81 imp gal) external tanks
Internal bomb bay
600 kg (1,323 lb) maximum, 500 kg (1,102 lb) normal; bombs stowed vertically, which capped the size of any individual weapon
Structure
All-metal stressed skin — the first stressed-skin aircraft the Soviet Union built in quantity, and the design that taught the industry how

Performance

Maximum speed
423 km/h (263 mph) at 4,000 m (13,120 ft)
SB 2M-103 maximum speed
450 km/h (280 mph) at 4,100 m (13,450 ft); the SB bis 3 with underslung radiators reached 446 km/h (277 mph) on test
ANT-40 IS prototype
402 km/h (250 mph) on later 1935 test flights, from 378 km/h (235 mph) on the first
Time to 5,000 m
8.6 min (to 16,400 ft)
SB 2M-103 climb
1,000 m in 1 min 48 s (3,280 ft); 9,000 m (29,530 ft) in 32 min
Service ceiling
9,560 m (31,365 ft) — SB 2M-103 9,300 m (30,510 ft)
Range
1,500 km (932 miles) — SB 2M-103 2,300 km (1,430 miles)
Record altitude
12,246 m (40,177 ft) with a 1,000 kg (2,205 lb) load, set by M. Yu. Alexeev on 2 September 1937 in an M-103 aircraft
Tactical altitude, Khalkhin Gol
Above 6,100 m (20,010 ft) — the height at which Nakajima Ki-27s struggled to reach the formations in 1939
What it outran in 1936
Fiat CR.32 375 km/h (233 mph); Heinkel He 51 330 km/h (205 mph). Only a diving attack from above worked against it.
What outran it by 1940
Bf 109E-3 560 km/h (348 mph). The margin did not narrow; it reversed, and by a wider gap than it had ever held.

Propulsion & systems

Engines
Two Klimov M-100A V-12 liquid-cooled, licence-built Hispano-Suiza 12Ybrs
Power
642 kW (860 hp) each — M-100 560 kW (750 hp); M-103 716 kW (960 hp); M-105 in the MMN 783 kW (1,050 hp)
Propellers
Three-blade ground-adjustable metal — the first SB 2M-100 had two-blade fixed-pitch units; the 2M-103 eighteenth series introduced VISh-22 variable-pitch propellers
Cooling
Honeycomb frontal radiators with thermostatically controlled shutters; moved beneath the engines from the SB bis 3 onwards, worth roughly 25 km/h (16 mph)
Crew protection
None — no armour, no self-sealing tanks, no fire suppression. In 1936 that was a reasonable trade for speed. In 1941 it was a death sentence.
Nose station access
Belly hatch only — the forward gunner could reach his position only through a hatch under the fuselage, and could not get out of it in a ditching or belly landing. Foreign customers complained about this specifically.
Dorsal position
Open ring mounting until 1940, then an enclosed MV-3 turret; the change came four years after the type first met modern fighters
Undercarriage
Retractable main units with hard suspension that crews disliked; retractable ski gear was provided for on the 2M-103 tenth series, and fitted skis cost speed in the Winter War
Avia B-71
Avia-built Hispano-Suiza 12Ydrs engines in place of the Klimovs, and Czech 7.92 mm vz. 30 machine guns replacing the ShKAS in all three stations
Production plants
GAZ No. 22, Moscow (5,695) and GAZ No. 125, Irkutsk (1,136), plus three prototypes at the Tupolev bureau; Aero Vodochody and Avia in Czechoslovakia built 45 and 66
05The Tupolev SB’s operating costs: what a 1930s fast bomber cost to run

Unlike modern jets, the SB has no reliably recorded unit price or cost-per-flight-hour in accessible Western sources — Soviet 1930s industrial accounting was opaque, and figures that survive are inconsistent. What is clear is that the SB was deliberately designed for mass, low-cost production: it was simple enough to be turned out in the thousands at Factories No. 22 (Moscow) and No. 125 (Irkutsk), and cheap enough to be exported and licence-built abroad. For that reason we list its cost rows as “not reliably recorded (1930s)” rather than publish a spurious number.

06Variants of the Tupolev SB: SB-2M-100, SB-bis, Ar-2 and Avia B-71

Major variants included the early SB-2M-100 and SB-2M-100A; the improved SB-2M-103 / SB-bis with more power and refined aerodynamics; the transport conversions PS-40/PS-41; and the dive-bomber development Arkhangelsky Ar-2 (a deeper redesign sometimes treated as a separate type). Abroad, Czechoslovakia licence-built the SB as the Avia B-71, and examples later served with Bulgaria, Slovakia and — as captured aircraft — Finland and Germany. Variant designations and production splits differ between sources; the figures here are approximate.

Armament & payload

The SB defended itself with speed, and when the speed went there was nothing behind it

Four rifle-calibre ShKAS machine guns and a 600 kg bomb bay is a modest armament for a bomber that was, for about eighteen months, the most feared aircraft in Europe. That was the point of the design: the SB was a fast bomber in the doctrinal sense, an aeroplane fast enough that defensive armament was almost a formality. The nose pair had so little traverse that they were near useless against a head-on pass; the radio operator had to serve both the dorsal and the ventral gun and could not be in two places; and the ventral hatch position was so awkward that it was often left unmanned. Fits varied by block and by operator: the enclosed MV-3 dorsal turret arrived only in 1940, and the Avia B-71 substituted Czech 7.92 mm vz. 30 guns throughout.

Gun

  • Four 7.62 mm ShKAS machine guns — two flexible in the nose, one dorsal, one ventral
  • The ShKAS fired at about 1,800 rounds per minute, the fastest rifle-calibre aircraft gun in service anywhere at the time, which is exactly the wrong virtue when the problem is stopping power
  • The nose mounting had limited traverse and was of little use against frontal attacks; later production reworked it for a better field of fire
  • One man worked both the dorsal and the ventral gun. Japanese Ki-27 pilots at Khalkhin Gol identified this and attacked from the blind quarter
  • Avia B-71: a single 7.92 mm vz. 30 in the nose replacing the ShKAS pair, with the same weapon dorsally and ventrally

Air-to-air

  • None. The SB carried no offensive air-to-air weapon of any kind and was never intended to
  • The one attempt to arm the airframe for air combat was the ANT-46 (Air Force designation DI-8) heavy fighter of 1935: two 100 mm recoilless rifles in the outer wings, four fixed nose guns, one flexible gun aft
  • The DI-8 died with Leonid Kurchevsky's recoilless-rifle programme and his arrest, and no armed-fighter SB followed
  • What the type used against fighters was altitude and, at Khalkhin Gol, a deliberate move to operate above 6,100 m where the Ki-27 could not comfortably follow

Air-to-surface guided

  • None. Nothing of the kind existed in any air force when the SB entered service, and the type was long obsolete before guided weapons appeared
  • The Soviet answer to the accuracy problem was mechanical, not electronic: dive bombing
  • The SB-RK, with slotted flaps usable as dive brakes and radiators buried in the wing, entered production as the Arkhangelsky Ar-2 — 200 built
  • The Ar-2 was in turn overtaken by the Petlyakov Pe-2, which is where the SB's line properly ends

Bombs

  • 500 kg (1,102 lb) normal internal load; 600 kg (1,323 lb) maximum, as six 100 kg FAB-100
  • Alternatively six 50 kg (110 lb) weapons in the same bay
  • Two 250 kg (551 lb) FAB-250 on external wing racks on later production aircraft
  • Bombs were stowed vertically in the bay, which limited the size of any single weapon and did nothing for release accuracy
  • By contrast the Ar-2 derivative could lift 1,500 kg (3,307 lb) externally — a measure of how conservatively the original bay had been sized

Rockets

  • None. No rocket armament was standard on the SB in Soviet service
  • The type had no rocket-assisted take-off provision either, despite operating from rough forward strips on skis in winter
  • Soviet RS-series air-to-ground rockets of the period went to fighters and ground-attack types, not to the fast bomber
  • The nearest thing to rocketry in the family was the abandoned DI-8's recoilless rifles, which are a different and much stranger idea

Pods & other stores

  • Depth charges on Finnish SBs of Lentolaivue 6 — the first air-dropped depth charges used in combat anywhere
  • Two 368-litre (81 imp gal) external fuel tanks on the SB 2M-103 tenth series
  • Retractable skis for operation from snow-covered fields; they cost speed and made an already vulnerable aeroplane slower
  • Cameras in the bomb bay were proposed for the ANT-49 long-range reconnaissance variant, cancelled before a prototype
  • Glider-towing and supply-dropping fittings on aircraft relegated to second-line work from late 1941

Three typical loadouts

Grupo 12, Spain, winter 1936–37
Six 100 kg bombs internal, no external stores, four ShKAS with full ammunition. Cruise high and fast and simply leave the Fiat CR.32s and He 51s behind. For roughly a year this worked, and Nationalist and Condor Legion pilots could only intercept by diving from above.
Chinese and Soviet volunteer units, Battle of Wuhan, 1938
500 kg internal, formations at altitude, long transits. The same tactic and the same aeroplane, but now against Japanese fighters that had closed the gap, and losses heavy enough to force the Chinese SB units temporarily out of combat.
Western Front, June 1941
500 kg internal, no escort, low level, attacking German armour. The SB was slower than everything hunting it, unarmoured, with no self-sealing tanks and a single gunner covering two positions. Within days survivors were pushed onto night attacks.

Sourcing caveat: bomb-load figures vary between 500 kg and 600 kg depending on whether the source quotes the normal or maximum internal case, and external wing racks were not fitted to every block. Height is quoted as both 3.60 m and 4.24 m in reputable tables. Gun counts are stable at four ShKAS, but some sources describe them as "three stations" because the nose pair sits on one mounting. Production totals are discussed in the closing note below.

Variants

The SB was rebuilt again and again to keep pace with fighters, and never managed it twice

In October 1936 a batch of thirty-one SBs arrived at Cartagena and flew their first mission against Tablada airfield at Seville on the 28th. What followed was one of the genuine shocks of pre-war aviation: a twin-engined bomber that the biplane fighters sent to intercept it simply could not catch. The Fiat CR.32 managed 375 km/h and the He 51 rather less; the SB did 423 km/h at 4,000 m. Interception required diving on it from above with an altitude advantage already in hand, which meant knowing where it would be. For a season the SB was as close to uninterceptable as any bomber has been, and the effect on doctrine was enormous — the fast unescorted bomber that would always get through stopped being a theory and became something people had watched.

The correction was brutally quick. Messerschmitt Bf 109s reached the Condor Legion in 1937 and the margin vanished inside a year; by the end of the Civil War 73 of the 93 SBs delivered to Spain had been lost, 40 of them to enemy action. The Soviet Union kept building anyway, because there was nothing better ready: almost 4,000 came out of the factories in 1939 and 1940 alone. On 22 June 1941, 94 per cent of the Soviet operational bomber force was SBs, with 1,500 to 2,000 of them in the western border districts. Most were destroyed on the ground or thrown away in unescorted low-level attacks in the opening weeks, and by December 1941 almost all had been lost or replaced.

Abroad the type had a longer and stranger life. China received 62 in autumn 1937, another 60 in early 1938 and 100 more in 1941, and Soviet crews flew them on the celebrated 23 February 1938 raid on Japanese airfields in Formosa. Czechoslovakia bought 60 Soviet-built aircraft and a licence, but had not completed a single Avia B-71 by the time the Wehrmacht arrived in March 1939 — the aircraft ended up serving the Luftwaffe, Slovakia and Bulgaria instead. Finland is the neatest irony: the Finns salvaged Soviet SBs downed on their own soil during the Winter War, repaired eight, bought sixteen more from German war booty, and flew twenty-four of them against the Soviet Union with Lentolaivue 6, losing seven to accidents and none in combat.

ANT-40 RTs (1934 / 1)
First prototype, Wright Cyclone radials and a 19.00 m wing; first flight 7 October 1934. Not pursued.
ANT-40 IS (1934–35 / 2)
Hispano-Suiza 12Y engines and the longer 20.33 m wing. The second aircraft became the production prototype — and the one covered in placards listing its faults.
SB 2M-100 (1936)
First production model. M-100 engines, two-blade fixed-pitch propellers, wing area raised to 56.7 m2.
SB 2M-100A (late 1936–1938)
M-100A of 642 kW (860 hp) and three-blade propellers. Sometimes called the SBbis. The Spanish and first Chinese aircraft.
SB bis, bis2, bis3 (1937–38 / 3)
M-103 prototypes. The bis3 moved the radiators under the engines and reached 446 km/h, and its nacelles went into production aircraft.
SB 2M-103 (1938–41 / tenth, fourteenth and eighteenth series)
The main late version: stronger structure, external tank and ski provision, then revised nacelles, then the MV-3 dorsal turret and variable-pitch propellers.
USB (1937–41 / over 120)
Dual-control trainer with the instructor in an open nose cockpit replacing the navigator. Built because converting pilots onto the SB was proving dangerous.
SB-RK, produced as Arkhangelsky Ar-2 (1940–41 / 200)
Dive-bomber development with reduced-span wings, slotted dive-brake flaps and wing-buried radiators. Superseded by the Pe-2.
Avia B-71 (1937–39 / 111 Czech-built)
Licence-built SB 2M-100A with Avia-built Hispano-Suiza 12Ydrs engines and vz. 30 guns. 45 by Aero Vodochody, 66 by Avia; sources also cite 101 as the total.
PS-40 and PS-41 (1938–40 / 100 plus conversions)
Aeroflot freighters stripped of military equipment, carrying cargo or six passengers; PS-41 from SB 2M-103 airframes.

Production and survivors. The production total is unsettled. Adding the plant figures gives 6,945 (5,695 at Moscow, 1,136 at Irkutsk, three Tupolev prototypes, 111 in Czechoslovakia), while the figure 6,656 is also widely printed and the Czech sub-total is variously given as 101 or 111. Either way this is one of the largest bomber runs of the 1930s. Very little survives. Two original airframes are on public display in Russia: one at the Central Air Force Museum at Monino, recovered from the Yuzhne Muiski range in the Baikal region in the late 1970s and restored by volunteer Tupolev employees before being unveiled in April 1982, and a second at the museum at Verkhnyaya Pyshma. No original SB is airworthy. The aircraft under construction by the La Senia Airfield Association in Catalonia is a new-build reproduction, not a restored original, although Russia has donated period components towards it. The Spanish Nationalist survivors were scrapped in 1948 and the Finnish machines in 1950, which accounts for most of the rest.

Timeline

The Tupolev SB from prototype to obsolescence

1934

ANT-40 first flight

Tupolev’s fast-bomber prototype flies. Its all-metal monoplane layout and high speed mark it as one of the most modern combat aircraft in the world.

1936

Service & Spain

The SB enters Soviet service and is rushed to Spain, where Republican “Katiuska” bombers outrun Nationalist fighters almost at will.

1937

War in China

SBs reach China, flown by Soviet “volunteer” crews and the Chinese Air Force against Japanese forces.

1937–38

The Bf 109 arrives

In Spain the Messerschmitt Bf 109 catches and kills SBs for the first time, ending the era of the untouchable fast bomber.

1939

Khalkhin Gol & the Winter War

SB regiments bomb Japanese forces at Khalkhin Gol, then raid Finland in the Winter War — where losses to fighters and flak mount sharply.

1940

Ar-2 dive-bomber

The Arkhangelsky Ar-2 dive-bomber derivative appears, an attempt to keep the ageing design relevant.

1941

Barbarossa catastrophe

By the German invasion the SB is obsolete. Unescorted daylight regiments are cut to pieces by the Luftwaffe in the opening weeks of the war.

1942–45

Night work & retirement

Surviving SBs are relegated to night bombing, transport and training as newer types replace them; a handful endure in museums today.

Stories & Eyewitnesses

Twelve things worth knowing about the Tupolev SB

Spain

The “Katiuska” that outran everything

For a while over Spain, no Nationalist fighter could catch it.

How the SB dominated early Spanish skies
In 1936 the SB was faster than the fighters sent to intercept it. Republican crews could cross the front, bomb, and be gone before biplane fighters could climb to meet them — a psychological shock that made the “fast bomber” idea look unbeatable, right up until the Bf 109 arrived.
Turning point

The day the Bf 109 changed the maths

A new German fighter finally ran the SB down.

Why one aircraft ended the SB’s reign
The Messerschmitt Bf 109, blooded in Spain with the Condor Legion, was the first fighter that could reliably catch and destroy the SB. Overnight the bomber’s entire survival strategy — outrun the enemy — collapsed. It was a preview of the SB’s fate in 1941.
China

Soviet “volunteers” over China

SBs fought Japan years before Pearl Harbor.

The SB’s long, half-forgotten war in Asia
From 1937 the SB was a mainstay of the air war against Japan, flown by Soviet “volunteer” crews and by the Chinese Air Force. Hundreds were supplied over several years. It is one of the least-remembered but longest-running combat careers of any 1930s bomber.
Khalkhin Gol

Bombing at the edge of the map

High over the Mongolian steppe in 1939.

The SB at the Khalkhin Gol border war
During the 1939 clashes with Japan at Khalkhin Gol, SB regiments bombed Japanese positions, sometimes operating at high altitude to stay above the nimble Ki-27 fighters. The campaign was a proving ground for Soviet tactics that would matter two years later.
Winter War

Raiding Finland in the snow

Finnish fighters and flak began to bite hard.

The Winter War and the SB’s rising losses
In the 1939–40 Winter War the SB carried much of the Soviet bombing effort against Finland. Finnish fighters and anti-aircraft fire claimed a large number — Finnish sources claimed around two hundred — an early warning that the type’s day was ending.
1941

The massacre of the SB regiments

Barbarossa turned the fast bomber into a target.

How catastrophic the 1941 losses really were
When Germany invaded in June 1941 the SB still equipped the bulk of the Soviet bomber force. Sent out in daylight, often without escort, entire formations were destroyed by German fighters and flak. The losses in those first weeks were among the worst of the early war.
Numbers

The most-produced bomber of the 1930s

More than six thousand were built.

Just how many SBs came off the line
Production is usually estimated at more than 6,600 aircraft — some sources go higher — built mainly at Factories No. 22 and No. 125. That total makes the SB very probably the most-produced bomber of the entire 1930s, and one of the most-produced Soviet aircraft of its era. Exact figures vary between sources.
Licence

Built in Czechoslovakia as the Avia B-71

A Soviet bomber made under Western skies.

The Avia B-71 and other export SBs
Czechoslovakia licence-built the SB as the Avia B-71, alongside Soviet-supplied machines. Export and licence examples later served Bulgaria and, after 1939, some ended up with Slovakia. It is a rare case of a Soviet combat type being manufactured in central Europe.
Captured

Flown by its enemies

Finland and Germany used captured SBs.

The SB in Finnish and German hands
Finland operated a mix of captured Winter War SBs and German-supplied examples, using them into the Continuation War in secondary roles. Germany and others flew captured aircraft too. Being flown by the very air forces that had shot it down is a strange coda to the SB’s career.
Engineering

A French engine with a Soviet accent

The V12s were Hispano-Suiza in origin.

The Klimov M-100/M-103 story
The SB’s Klimov M-100 and M-103 V12s were licence-derived from the Hispano-Suiza 12Y. Light and streamlined, they suited a fast bomber — but their liquid cooling made them fragile under fire. The same engine family powered a whole generation of Soviet aircraft.
Ar-2

The dive-bomber that tried to save it

A redesign chased relevance as the SB aged.

From SB to Arkhangelsky Ar-2
As the basic SB fell behind, Arkhangelsky developed the Ar-2, a dive-bomber derivative with a shorter wing and refined aerodynamics. Only modest numbers were built before the Petlyakov Pe-2 took over the role, but the Ar-2 shows how hard designers worked to extend the airframe’s life.
Survivors

The few that are left

A handful survive in Russian museums.

Where you can still see a Tupolev SB
Very few SBs survive. Static examples restored from wrecks recovered in Russia are displayed at the Central Air Force Museum at Monino and at Verkhnyaya Pyshma. Reports of an airworthy example circulate, but we could not firmly confirm a currently-flying SB — treat “airworthy survivor” claims with caution.
Gallery

The Tupolev SB in pictures

Tupolev ANT-40, the SB fast-bomber prototype of 1934
The ANT-40 prototype that became the SB. Public domain, via Wikimedia Commons
Soviet Tupolev SB bombers over Helsinki during the Winter War, 1939
Soviet SB bombers over Helsinki during the Winter War, 1939. Public domain, via Wikimedia Commons
A captured Tupolev SB in Finnish Air Force markings
A captured SB in Finnish Air Force service (SA-kuva archive). Public domain, via Wikimedia Commons
Klimov M-103 V12 engine of a Tupolev SB-bis
Klimov M-103 engine of an SB-bis, a Hispano-Suiza 12Y derivative. Photo: MKFI, public domain, via Wikimedia Commons
Preserved Tupolev SB 2M-100A airframe on museum display
Preserved SB 2M-100A. Photo: Alan Wilson, CC BY-SA 2.0, via Wikimedia Commons
A Tupolev SB brought down in combat
A downed SB — the type suffered heavy wartime losses. Photo: Willi Ude, CC BY-SA 3.0, via Wikimedia Commons
Watch

The Tupolev SB in one short history

“Tupolev SB – The Soviet Bomber That Changed the Skies” (Iron Wings Archive). A concise type overview; note that this is a niche aviation-history channel with a modest audience (a few thousand views) — no large-scale documentary of the SB exists, which is itself telling of how overlooked this once-revolutionary bomber has become.

Operations

Where the Tupolev SB flew and fought

Combat Record

The Tupolev SB in combat

Few aircraft packed so much combat into a short front-line life. The SB fought in Spain, China, at Khalkhin Gol and in the Winter War before the Second World War even began — then paid a terrible price in 1941, when the fast bomber of 1934 had become an easy target. Figures below are best estimates and vary between sources.

~6,600+ builtmost-produced 1930s bomber (est.)
4 conflictsSpain, China, Khalkhin Gol, Winter War — before WWII
1941catastrophic losses in Barbarossa’s opening weeks

See also: the Petlyakov Pe-2, the bomber that replaced it

Questions & Answers

Tupolev SB: your questions answered

Can I fly in a Tupolev SB?

No. The Tupolev SB is a retired 1930s bomber with only a few static survivors in museums, and MiGFlug does not offer flights in one — there is no airworthy example on any public flight line. However, you can fly in several genuine military jets today, from the L-39 Albatros to the MiG-29. See what is currently bookable at migflug.com/flights-prices.

Was the Tupolev SB really faster than fighters?

Yes — at first. When it entered service around 1936, the SB’s top speed of roughly 450 km/h exceeded that of most fighters then in service, so in level flight it could simply outrun interceptors. That advantage was real but temporary: the Messerschmitt Bf 109, which appeared in Spain, could catch it, and by 1941 the SB was slower than every front-line fighter it faced.

What does “SB” mean, and what are ANT-40 and SB-2?

SB stands for Skorostnoi Bombardirovshchik — Russian for “fast bomber.” ANT-40 was the Tupolev design-bureau prototype designation, and SB-2 is the common Western name for the production aircraft. They all refer to the same basic type.

Why did the Tupolev SB suffer such heavy losses in 1941?

The SB was designed on the assumption that speed alone would protect it, so it had light defensive armament, no crew armour and unprotected fuel tanks. By 1941 it was slower than German fighters, and Soviet regiments were often sent out in daylight without escort. The result was catastrophic losses in the opening weeks of Operation Barbarossa. Exact loss figures vary between sources.

What engines did the Tupolev SB use?

Two Klimov M-100 and later M-103 liquid-cooled V12 engines — Soviet-built derivatives of the French Hispano-Suiza 12Y. The M-103 produced roughly 960 hp each. Power figures vary slightly between sources and sub-variants.

What was the Avia B-71?

The Avia B-71 was the Tupolev SB built under licence in Czechoslovakia. Around 60–66 were produced there, in addition to Soviet-supplied machines; examples later served with Bulgaria and Slovakia. It is a rare instance of a Soviet combat aircraft being manufactured in central Europe.

How many Tupolev SBs were built?

Production is usually estimated at more than 6,600 aircraft, with some sources citing figures approaching 6,900 including licence-built examples. That very likely makes the SB the most-produced bomber of the 1930s. As with most Soviet interwar figures, exact totals are uncertain, so treat the number as an estimate.

Are there any surviving Tupolev SBs?

Only a few. Static aircraft, restored from wrecks recovered in Russia, are displayed at the Central Air Force Museum at Monino and at Verkhnyaya Pyshma. Claims of a fully airworthy, currently-flying SB circulate online, but we could not firmly verify one — so we treat the “airworthy survivor” story with caution.

You can't fly the Tupolev SB

The SB is grounded for good.
These fighters are not.

You can’t strap into a 1930s Soviet fast bomber — but you can fly a real military jet today. Pick your aircraft and your country:

See all flights & prices
Related Aircraft

More Soviet warplanes

Soviet bomberIlyushin Il-4The long-range Soviet bomber that carried the war to Berlin in 1941 — a contemporary of the SB with a very different, more durable career.Open exhibitSoviet bomberPetlyakov Pe-2The fast, capable dive-bomber that replaced the SB in Soviet service and became one of the best Allied tactical bombers of the war.Open exhibitSoviet fighterPolikarpov I-16The stubby Soviet monoplane fighter that fought alongside the SB in Spain, China and 1941 — another once-modern design overtaken by events.Open exhibit
Sources & Further Reading

Sources & further reading