Development of TB-3 heavy bomber with doubled takeoff weight and
doubled wing area. Four of six engines were installed in the thick
(2m!) wing, two - in a tandem above the fuselage. Project started even
before the TB-3 was ready.
TB-4 was built following dominating theory stating that efficiency of
bomber increases with its payload. Low speed had to be compensated by
strong defensive weapons and capability of huge aircraft to withstand
serious punishment from enemy fighters. Even heavier aircraft were
considered (to emerge later as ANT-26 and ANT-28 projects), with
wingspan approaching 100m and payload of 25tons.
The aircraft novelties included two enormous 5x1.8x1.8m bomb bays in
the fuselage (designed by K.P.Sveshnikov and V.M.Myasichev). Such a
bomb bays made a 'World Record' - none other contemporary bomber was
First flight was performed by M.M.Gromov on July 3, 1933. Flight test
program (pilots Riazanov, Stefanovsky, Nukhtikov) was fulfilled in a
short time - on September 29, 1933. Performance of TB-4 was found poor.
In-wing engines wasted too much power to blow 2m thick wing, tandem
installation was inefficient (typical for tandems), and as a result
aircraft was badly underpowered.
Installation of more powerful 1250hp M-35 engine was suggested, but
TB-4 was not accepted for production, but gained experience helped to
finish even larger ANT-20 "Maksim Gorky" in record short time.
Wing span, m
Wings area, m2
Maximum speed, km/h
Cruising speed, km/h
Service ceiling, m
6 PE M-34
6 У 830
2 20-mm cannons, up to 10 7.62-mm machine-guns
10000-11800 kg bombs