"In 1965 in the division of engineering designs OKB they prepared the preliminary design of the aircraft Tu-148, which had to enter into the composition of the new aviation-missile complex of distant interception
Tu-148-100. Medium it was intended to equip radar «Groza-100» and to arm with
rockets K-100. On the project, Tu-148 it had variable sweep wing and two turbojets of the type
RD-19R-2 (РД-19Р-2) with the thrust on the afterburner 14200 kg. Interceptor had to fly at the heights of 50-100 m with a velocity of 1400 km/h, and at the heights of 16000-18000 m with a velocity of 2500 km/h. Distance at cruise had to be about 5000 km, and in the supersonic mode – 2500 km special feature Tu-148 was the for the first time developed IRST system for control of rocket armament.
«Groza-100» with a diameter of the antenna mirror of 2m onboard equipment of interceptor it made it possible to use it in the autonomous mode. Complex could be used for the interception of aerial targets on the distant approaches to the territory of the USSR and for PVO of areas with the under-developed or disabled ground-based navigation and airport systems. Thus, the problems of complex Tu-128 it was intended to solve at the new technical level."
https://testpilot.ru/en/rossiya-e/tupolev/148-e/
