After the success reached with the prototype as the first supersonic airliner on the air, it was necessary to upgrade the design for to correct some detected problems and to exceed the supersonic flight range of 3,500 km.

To improve the aerodynamic of the plane at supersonic mode the wing was deeply modificated and his surface increased. The length of the fuselage was also increased to transport 150 passengers and the engines replaced by the upgraded model NK-144A.

One of the most important changes was the new configuration of engines in two different and separate nacelles with two engines and their own intakes each one. This option solved the problems of vibrations and hight temperatures in the bottom part of the fuselage. A new and original system of retraction of the main landing gear was developed because it was now placed between the two engines.

Another important change was the addition of two canards in the forward part of the fuselage to provide stability in landing and take-off. With all these changes the take-off weight was increased until 190 tons.

CCCP-77101 was the last plane produced at MMZ “Opyt” plant and assembled at Zhukovsky, and the first model TU-144S. On April, 1973 was used as scene of a press conference.