The Council of the People's Commissars directed Alekseyev and other designers to develop jet fighters using more powerful engines than the captured German Jumo 004 and the BMW 003 and their Soviet-built copies.

[1] The I-21 was a twin-engined, all-metal, single-seat jet fighter, with straight laminar flow wings, mid-set on a circular fuselage.

A hydraulically retractable tricycle undercarriage was fitted, using twin wheels for the nose and main landing gear.

Even replacing the BMW 003 with the slightly more powerful (900 kgf (8.8 kN; 2,000 lbf)) Jumo 004 would not allow the I-210 to meet the speed requirement and the project was cancelled before any metal was cut.

While one of the two airframes initially produced was used for static testing, the other was fitted with 1,300 kgf (13 kN; 2,900 lbf) Lyul'ka TR-1 turbojet engines because the intended TR-2 was not available.

The substitution of the centrifugal-flow Derwent for the axial-flow TR-1 forced the redesign and enlargement of the nacelles to accommodate the larger engine.

Despite good results from flight testing, the I-215 lost out in production orders to the newer generation of swept-winged fighters.