The aircraft had been assembled after the delivery and undergone debugging and system testing at Sukhoi's testing facility for five months. In particular, the aircraft was for the first time fitted with a Tikhomirov-NIIP AESA radar prototype, whose functioning as part of the avionics suite was tested. During mid-June, the T-50-3 was taken to the airfield and began its first taxi runs. Once all faults had been ironed out, a decision was made for a check flight, and Sergei Bogdan took the aircraft off LII Gromov's tarmac for the first time at about 15.20 on 21 June 2012. The check ride took about an hour, with the plane and its system functioning up to snuff. In the near future, the T-50-3 will start flight trials of the AESA radar and other systems that has not been installed in the earlier prototypes.

Now the second PAK FA prototype is involved in the flight tests too. Sergei Bogdan first flew it on 3 March 2011. A month later, the T-50-2 was brought to Zhukovsky and has been flying in the Moscow Region since mid-August. It has logged about 50 sorties. As far as the first flying prototype is concerned, it has been debugged since its being unveiled at MAKS 2011 in August last year. By then, it had had about 75 sorties under its belt, starting from the very first one in Komsomolsk-on-Amur on 29 January 2010 (the T-50-1 had flown in Zhukovsky since April 2010).

The 100th test flight under the PAK FA test programme was conducted on 3 November 2011 by Sergei Bogdan flying the T-50-2. To date, the total number of the flights logged by the three prototypes is around 130 and will keep on increasing owing to the third prototype having joined the trials. The fourth aircraft now in assembly by KnAAPO is expected to be flight-tested in Komsomolsk-on-Amur in autumn. It then will join the first three in Zhukovsky after its ferry flight under its own power from the Russian Far East to the Moscow Region, if all goes to plan.

As is known, in February, Col.-Gen. Alexander Zelin, the then-commander of the Russian Air Force, told the RIA Novosti news agency in his interview that 14 PAK FA fighters were planned to be made and put into tests by 2015. The first four flying prototypes are to be joined by two more next year, after which KnAAPO will launch the manufacture of the low-rate initial production batch. The official PAK FA test phase is supposed to commence at the Air Force State Flight Test Centre in Akhtubinsk with the official objective of handing early planes over to the customer. According to media reports, about 60 production-standard PAK FA fighters are planned to be fielded since 2016 through 2020. Obviously, the deliveries will continue beyond 2020.