The Tupolev I-4 (Development name ANT-5) was a Soviet fighter biplane. It was the first aircraft designed by Pavel Sukhoi.

ANT-5 was a prototype of I-4 sesquiplane single-seat fighter.

I-4 differed from ANT-5 by redesigned (to decrease drag) engine howling, added rocket launchers on upper wing and increased tailfin.

The lower wing was nothing more than an attachment for the wing struts; it was (almost) removed in the second series (I-4bis), used as a parasite fighter in Zveno experiments with TB-3 bomber.

The I-4 was the first Soviet all metal fighter.

One 480hp M-22 engine.

Total 369 were built.

In service in 1928-1933.

Development of 1927.

External links:

http://www.aviation.ru/Tu/#ANT-5