Tupolev SB - Variants

Variants

• ANT-38 – Unbuilt 1934 proposal for high speed bomber – possibly related to ANT-41.
• ANT-40 RTs (Rayt Tsiklon) or SB :first prototype with 545 kW (730 hp) Wright-Cyclone engines and with 19.0 m (62 ft 4 in) wingspan. It was completed in September 1934, making its first flight on 7 October 1934. It was damaged in a forced landing and rebuilt with 670 kW (900 hp) Tumansky M-87 engines, and a second set of test flights were made from 5 February to 31 July 1935. Development not continued as ANT-40 IS was superior. Used as experimental (ski gears, etc.) model.
• ANT-40 IS (Hispano-Suiza): Prototypes powered by 560 kW (750 hp) Hispano-Suiza 12Y engines, and with longer span (20.3 m (66 ft 7¼ in) wings. Two built, with the first ANT-40₁ flying on 30 December 1934, reaching 378 km/h (235 mph) during initial tests and 402 km/h (250 mph) during later flights. Second example, ANT-40₂, with modified wings and tail emerged in September 1935 and served as a production prototype.
• SB 2M-100 – first production model. Wing area increased to 56.7 m2 (610 ft2). Equipped with Klimov M-100 engines (the Hispano-Suiza 12Y built under licence) driving two-bladed propellers.
• SB 2M-100A – new M-100A engines of 642 kW (860 hp), driving three-bladed propellers. Produced from late 1936. Sometimes unofficially referred to as the SBbis.
• SB 2M-100A modernizoravannyi – new rear gun installation with MV-3 dorsal turret. Tested in May 1937. Accepted, but no production.
• SB-bis – prototype powered by 716 kW (960 hp) Klimov M-103 engines, dual controls and variable pitch propellers. It flew in September 1937, but increased weight lead to reduced performance.
• SB-bis2 – M-103 powered prototype with polished wings. Little increase in performance. No production.
• SB-bis3 – third M-103 powered prototype, with new engine nacelles with radiators relocated under engines rather than the frontal radiators fitted in earlier aircraft. Tested from 1 November 1937-17 January 1938, with testing showing maximum speed increasing to 446 km/h (277 mph). Improvements later incorporated into production aircraft.
• SB 2M-103 — 10th series. 1938 production version with M-103 engines fitted with original frontal radiators and strengthened structure. Fitted with emergency flight controls for navigator, provision for retractable skis, and for two 368 litre external fuel tanks.
• SB 2M-103 – 14th series. Late 1939 production, with M-103 engine and revised nacelles and radiators as tested in SBbis3.
• SB 2M-103 – 18th series. Further improved production version, with fixed radiator intakes and partially polished wings. VISh-22 three-bladed variable-pitch propellers. Fitted with MV-3 dorsal turret.
• SB 2M-104 — Approximately 30–50 aircraft were completed with M-104 engines, but engine not in series production.
• SB 2M-106 — A few aircraft completed with M-106 engines, but engine not in production.
• USB – dual control trainer, with the instructor sitting in an open cockpit in the nose replacing the navigator. Over 120 built, powered by the M-100A or M-103.
• SB-MN (Men'she nesushchye – reduced area) or MMN (Modifikatsiya men'she nesushchye) — second generation level bomber powered by 783 kW (1,050 hp) M-105 engines and with new wings with NACA 22 high lift airfoils, reduced wing area and span (18.0 m (59 ft 0¾ in). One built.
• SB-RK (Rasresnoye krilo – slotted wing) – Dive bomber delevloped in parallel with SB-MN. Same wings as SB-MN, but with large slotted flaps usable as dive brakes. The cooling radiators were buried within the wings, with an air intake on the leading and the exhaust on the wing's upper surface. Equipped with three ShKAS machine guns, and it could carry six 100 kg (220 lb) bombs or two 250 kg (550 lb) bombs internally or 1,500 kg (3,300 lb) bombs externally. Ordered into production as Arkhangelskii Ar-2. 200 built before it was superseded by the Pe-2 and Tu-2.
• SBB-1 — Archangelskii's last iteration of the SB, based on SB-MN and -RK, with even smaller wings (16.0 m (52 ft 5⅞ in) span) twin tail and other changes. Alternative designation B. One prototype flown 1940 but no production.
• Avia B-71 – SB 2M-100A licence built in Czechoslovakia.
• PS-40 – cargo version for Aeroflot, powered by M-100A engines and with all military equiment removed. Capable of carrying cargo or six passengers. 100 supplied during 1938.
• PS-41 – Conversion of SB 2M-103 as freighter for Aeroflot. PS-41bis fitted with underwing fuel tanks.
• Pterodactyl – SB 2M-103 fitted with fixed tricycle landing gear. One converted 1940.
• ANT-46 – two-seat heavy fighter, similar to ANT-40₁, but powered by two imported 597 kW (800 hp) Gnome-Rhône 14K engines and armed with two 100 mm recoilless rifles in outer wings, four fixed machine guns in the nose, and one flexibly mounted machine gun in the observers cockpit. One prototype, with Air Force designation DI-8 first flown in August 1935, but abandoned after abandonment of Leonid Kurchevsky's recoilless rifle projects and his subsequent arrest.
• Tupolev ANT-41 – unrelated Torpedo bomber with similar layout to SB but larger and more powerful. One built in 1936, abandoned after destroyed in crash due to severe flutter.