Soviet Heavy Fighters 1926–1949

The idea behind the “air cruiser” design dates back to the closing stages of World War 1, when it became apparent that newly-introduced heavy bombers required effective fighter cover along their entire route of flight. To perform the task effectively, a fighter design was needed with a speed at least matching that of the bombers, enough range to provide protection, heavy armament consisting of cannons and machine guns and, to top things off, agility to be able to successfully engage enemy fighters. It was also hoped that such a platform would be capable of performing reconnaissance missions, as well as engaging secondary targets, such as AAA positions protecting primary targets, or defeating enemy bomber formations. Although quite a few nations attempted to build such an aircraft, the task proved to be extremely complex and difficult.

 CiezkieSowieckie zd3

How the Steel was Tempered, or the birth of ANT-7 (R-6)

Operational use of the Ilya Muromets bomber in World War 1 provided a wealth of lessons learned, which demonstrated that the heavily armed aircraft was extremely difficult to engage by enemy fighters due to its defensive firepower having been projected in all directions. As such, it could prove to be a formidable weapon against enemy fighters in the role of an “air cruiser”. Unfortunately, Russia’s mixed fortunes towards the end of the war meant the idea was not pursued. A.N. Tupolev, however, never quite gave up on it and it was revisited many years later.
In the USSR the trigger that ultimately led to the development of “air cruiser” was the introduction of the TB-1 (ANT-4) bomber. As the new aircraft was just barely rolling off the production line, A.N. Tupolev was already busy ordering his design bureau staff to begin work on the new design. The team consisted of N.I Petrov responsible for fuselage design, V.M. Petlyakov who would work on the wing and landing gear and E.I. and I.I. Pogosski delivering the powerplant.
 

CiezkieSowieckie zd4

The new aircraft was designed as an all-metal, cantilever monoplane with corrugated metal skin. It was to be powered by a pair of 500 – 600 hp engines and operated by a crew of three. According to the design documentation, the machine, designated ANT-7, was to be a multi-seat escort fighter. The aircraft was essentially a scaled-down version of the TB-1. When the design was first presented to the VVS (Voyenno-Vozdushnye Sily – Soviet Air Force), the brass liked what they saw and proceeded to compile official tactical and technical requirements for the new machine. The first draft of the document was released on August 9, 1927 and required the payload capacity of 588 kg. It also classified the aircraft as a long-range reconnaissance platform, hence the military designation R-6 (rozvedchik – reconnaissance aircraft). Tupolev relentlessly lobbied the Air Force to introduce changes to the document that would emphasize the fighter role of the design and to tweak certain technical requirements. Those were not extraneous efforts – Tupolev was hoping that the official requirements would eventually more closely match the project already sitting on the drawing boards. On October 27, 1927 the changes were officially approved and the new machine was defined as a “multi-seat frontline fighter”.