In the early sixties the race started between east and west to produce and fly a supersonic airliner,
ending in the production of the Concorde and the "Concordsky" (Tu-144). Construction of both
types was started after many hours of design, material testing; many different models were made and used
in wind tunnel tests. Flying a scaled-down wing of similar plan form was suggested also in both projects,
the Concorde wing concept being tested on the BAC 221, flying in 1964.
The Tu-144 double-ogive wing concept was also to be tested and in 1965 the Mikoyan design bureau was
charged to produce the airframe. The aircraft (a redesigned MiG-21S known to the company designers as the
21-11) received the official designation MiG-21I (I for Imitator); in fact it was built on the MiG-21S
production line. The MiG-21I was the first and only MiG jet design with no tail plane and had a complete
new wing with the part ahead of the main spar easy replaceable so different shapes could be tested.
The -21S R-11F2S-300 engine was replaced by the higher-powered R-13-300 and the -21I had 17% more fuel
capacity, up to 5,985 lb (2,715 kg). The inability to lay down the exact shape of the wing and elevons,
and other details caused a delay of more than a year and the MiG-21I/1 (CCCP-1966) did only fly for the
first time on April 18, 1968 by O. Gudkov. It was also flown by the two Tu-144 test pilots Yelyan and
Kozlov four times each and it flew as a chase plane on the first flight of the Tu-144 on December 31,
1968.
The first MiG-21I crashed on July 28, 1970 flown by Victor Konstantinov while conducting unauthorized
aerobatics at low-level killing the pilot. The second aircraft, known as MiG-21I/2, had a 20.5 sq.ft
(1.9 sq.m) larger wing and with four elevons on each side instead of flaps and elevons. This aircraft
flew for the first time in 1969 with I. Volk at the controls; several leading-edge root extensions (LERX)
were tested. On the top of the fin and on the right-hand side canopy-fairing it had fairings carrying
cameras filming the tufted right-hand side wing.
In total 140 flights were made by the two MiG-21I’s; the second aircraft is preserved at Monino, Moscow.
It may be clear that due to the delayed maiden flight the MiG-21I it had no influence on the Tu-144
prototype wing lay-out.