Editing Tupolev Tu-144 (section)

===Use by NASA===
In the early 1990s, Judith de Paul, and her company IBP Aerospace brokered an agreement with Tupolev, [[NASA]], [[Rockwell International|Rockwell]] and later [[Boeing]]. They offered a Tu-144 as a testbed for NASA's High Speed Commercial Research program, which was intended to design a second-generation supersonic jetliner called the [[High Speed Civil Transport]].<ref>{{cite journal |last1=Huntington |first1=Tom |title=Encore for an SST |journal=Air & Space/Smithsonian |date=October–November 1995 |url=http://www.aviation.ru/Tu/144/story1/ASM_T144_ON95.html |archive-url=https://web.archive.org/web/20020911214606/http://www.aviation.ru/Tu/144/story1/ASM_T144_ON95.html |archive-date=11 September 2002 |access-date=29 May 2023 |url-status=live }}</ref> In 1995, Tu-144D No. 77114 (with only 82.5 hours of flight time) was taken out of storage and after extensive modification at a cost of US$350{{nbsp}}million, designated the ''Tu-144LL'' (where LL is a Russian abbreviation for Flying Laboratory, {{langx|ru|Летающая Лаборатория}}, ''Letayushchaya Laboratoriya''). The aircraft made 27 flights in Russia during 1996 and 1997.<ref name="NASA Tu-144LL" /> Though regarded as a technical success, the project was cancelled for lack of funding in 1999.

This aircraft was reportedly sold in 2001 online, but the aircraft sale did not proceed. Tejavia Systems, the company handling the transaction, reported that the deal was not signed as the replacement [[Kuznetsov NK-321]] engines also used in a [[Tupolev Tu-160]] bomber were military hardware and the Russian government would not allow them to be exported.<ref>{{cite web |title=ANN Exclusive: What Happened to the Tu-144 Sale? |url=http://www.aero-news.net/index.cfm?do=main.textpost&id=5d307b97-9ec1-4c9b-b3e7-796230514a8b |website=Aero-News Network |archive-url=https://web.archive.org/web/20230617230108/http://www.aero-news.net/index.cfm?do=main.textpost&id=5d307b97-9ec1-4c9b-b3e7-796230514a8b |archive-date=17 June 2023 |date=21 March 2022 |url-status=live |access-date=17 June 2023 }}</ref>

In 2003, after the retirement of Concorde, there was renewed interest from several wealthy individuals who wanted to use the Tu-144LL for a transatlantic record attempt, despite the high cost of a flight readiness overhaul even if military authorities would authorize the use of NK-321 engines outside Russian Federation airspace.{{citation needed|date=October 2015}}