First flew in 1981 as a Tu-144D. Modified to Tu-144LL testbed in 1996. Flew a joint series of test flights for NASA ending on 11.02.98, when it was retired.

This 144 was the last built and accumulated only 82 h flight time before being modified to LL (Flying laboratory) specifications. These mods included the installation of sophiticated instrumentation, upgraded engines and a crew emergency escape system that enabled the airframe to participate in a joint supersonic flight research program involving TupolevANTK and NASA.

THe SM variant is a two-pilot, ugraded version of the Tu-204 with new engines and avionics. This example was on static display at MAKS 2013.

First flew 13.4.81 as a Tu-144D and set several records in 1983. After fitment of new engines, made 32 flights under the NASA High Speed Research Program, the last on 11.2.98. Reportedly sold to a Texas businessman for $11m but remains wfu at Zhukovsky