Tupolev ANT-10 / R-7
Under the military designation R-7, a single ANT-10 was built as a possible alternative to Polikarpov's R-5, which first flew in 1928 and went on to have a production run of 4,995 in the 1930s.
Tupolev's project was an all-metal sesquiplane. The shortage of metal was one of the factors which worked in favour of the simple wooden airframe chosen by Polikarpov. For both aircraft the BMW-VI engine was specified, due to its planned Soviet production as the Mikulin M-17.
TsAGI began design work on the R-7 in 1928, when the R-5 was already flying. Its first flight was made on 30 January 1930, flown by Mikhail Gromov. As it was not appreciably better than the R-5, the programme was discontinued six months later.
Engine: 1 x BMW VI, 500hp
Max take-off weight: 2920 kg / 6438 lb
Empty weight: 1720 kg / 3792 lb
Wingspan: 15.2 m / 50 ft 10 in
Length: 10.9 m / 36 ft 9 in
Height: 3.6 m / 12 ft 10 in
Wing area: 49 sq.m / 527.43 sq ft
Max. speed: 235 km/h / 146 mph
Ceiling: 5500 m / 18050 ft