Hi all!
I have another info about ANT-32 index. The "Tupolev" ANT-32 was actually... Polikarpov I-13, the unbuilt I-15 precursor! To explain this, I must tell you some prehistory.
That was a time of many experiments in organization structure of Soviet aircraft engineering and industry. As one of them, on August 27, 1931 it was decided to merge the AGOS TsAGI (Tupolev) and TsKB of Zavod 39 (Polikarpov, Grigorovich) into one, extremely powerful design organization called TsKB TsAGI and headed by Sergei Ilyushin. This was done (aviation people nicknamed this event "marriage"), but the experiment wasn't successful. The new structure was very unwieldy; due to new complicated tasks, not centralization but even more specialization of design teams was demand of the time - so, not only the existing designers' brigades weren't merged but new specialized subdivisions appeared besides them.
Furthermore, Polikarpov didn't want to work under Tupolev, because their vision of some design problems and trends of aircraft development was too different (and it was difficult for such an experienced designer as Polikarpov to reconcile with Tupolev's domination). As a result of this conflict, in November 1931 Polikarpov was dismissed from his post of brigade chief. Almost half a year after this he stayed idle or was employed in secondary works, which was very hard feeling for him. Naturally, any Polikarpov’s project didn’t progress during this time.
In May 1932, there was an attempt to simplify the structure and its management. TsKB TsAGI was transformed into SOS TsAGI (СОС - Сектор опытного самолётостроения / Prototype aircraft construction sector). It included Design department known as KOSOS with Tupolev at the head, Department of introduction into series, Department of maintenance and flight tests, Prototype construction factory (Завод опытных конструкций - ЗОК / ZOK), etc. In turn, KOSOS was divided into many design brigades, each specialized on aircraft of particular class (fighters, bombers, seaplanes, etc.) This new structure was more appropriate, but it was still complicated enough because there were too many brigades! At the same time, former Polikarpov's No.3 brigade was merged with Sukhoi's No.4 brigade; Sukhoi became the chief, and Polikarpov one of his deputies. For the onlooker it could seem even worse (Polikarpov became subordinated not only to Tupolev, but also to Sukhoi), but actually these were good news for Polikarpov: he could return to active design work. But of course he wanted to work independently on his own projects.
Fortunately soon the situation changed for the better. As the SOS structure and management were still too complicated, it seemed fully reasonable to separate it back into two organizations. On January 13, 1933 Petr I. Baranov, the head of GUAP (Chief department of aircraft industry), made order to organize at Zavod No.39 a prototype design bureau for light aircraft, headed by Ilyushin. Ilyushin kept the old name for it (simply TsKB), but with KOSOS-like structure of independent specialized brigades. Thus, the old TsKB was reborn and Polikarpov headed No.2 Brigade specialized on fighter aircraft. Another TsKB brigades were headed by Kocherigin, Ilyushin himself, Chizhevsky, and Chetverikov (later Beriev).
And now back to ANT-32. When the “marriage” took place, Polikarpov worked on I-13 project; it would be a biplane (rather sesquiplane) fighter of mixed construction, with M-32 engine (600/750 hp). In the united TsKB TsAGI, the project was designated ANT-32 (all AGOS projects were labelled "ANT"!) But Tupolev had different look on the advanced fighter - he thought it must be all-metal (this was one of main causes for the conflict!), and the bureau was loaded with many other projects. After conflict with Tupolev, all works on I-13 / ANT-32 stopped; they restarted slowly just in Sukhoi brigade, although Sukhoi’s own I-14 (ANT-31) monoplane naturally had a priority. Start of M-32 bench tests gave some impulse to the program: the preliminary project was finally prepared and the calculations made. Under Tupolev's influence, Polikarpov agreed to make I-13 full-metal. Its projected characteristics were:
Wing area - 21 m2
Takeoff weight - 1450 kg
Maximum speed - 358 km/h (5000 m altitude)
Climbing to 7000 m - 10.7 minutes
Service ceiling - 9900 m
Armament - 4x 7.62-mm machine guns (ShKAS, or two ShKAS plus two Degtyarev DA)
In July 1932, Ilyushin proposed Polikarpov to design “I-14a” – a biplane backup for innovative Sukhoi I-14. In November it was decided to replace M-32 engine on I-13 project, due to its problems, with another engine type. Thus Polikarpov redesigned M-32-powered I-13 into I-14a with Wright Cyclone radial, implanting also gull wing and returning to his favourite mixed construction. The wooden mockup was built in parallel with I-14 mockup, and both were reviewed on the same special conference (December 8, 1932) presided by VVS deputy chief Yakov Alxnis. As a result, Alxnis made a decision to realize both projects, and I-14a obtained its definitive world-known designation – I-15. Polikarpov even got his own brigade (No.5) at KOSOS, but only for two months. Then he left KOSOS for the revived TsKB and continued his work there. On October 23, 1933 I-15 prototype was flown, already under TsKB-3 designation. But with some tolerances we can say that I-15, a common known Polikarpov design, was called “ANT-32” once!
Unfortunately I don’t have any pictures of I-13 / ANT-32 with M-32 engine. Instead I attach a 3-view of I-14a / I-15 preliminary project. As you can see, the initial design had retractable landing gear and enclosed cockpit!
Sources:
1. ANT-32 (I-13) / Aviatsiya I Kosmonavtika, No.1/1998, p.43 (Cycle „Under „ANT” & „Tu” marks” by V. Rigmant).
2. The aircraft industry in USSR (1917-1945). Volume 1. – Moscow, TsAGI, 1992. – P.9-10, 417-418.
3. Maslov Mikhail. I-15 fighter. – Moscow, Polygon, 2001 (“Kombat” almanac, issue 1). – P.3-4.