On April 7, 1979, Tom Knauff and R. Tawse set a world record with the IS-28 B2 glider, covering a distance of 829 kilometres on a predetermined out-and-return course from the Ridge Soaring Gliderport in Julian, Pennsylvania.

The IS-28B2 is depicted in the film Escape from New York (1981) The IS-28 was also produced as a motorglider, initially as just a powered version of the IS-28B2 (designated the IS-28M1) and then as the more radically redesigned IS-28M2.

This version had an entirely new forward fuselage offering side-by-side seating for the two occupants, wings relocated to a low-set position on the fuselage, and tailwheel undercarriage with main units that semi-retracted backwards into the wings.

The rear fuselage, empennage, and outer wing panels remained identical with the sailplane version.

The IS-29 is a single-seat sailplane that was designed and manufactured to complement training carried out in the IS-28 two-seater.