Perhaps the biggest surprise of the entire Russian military intervention in Syria was a week-long deployment of at least two (according to unsubstantiated reports: up to four) prototypes of the Sukhoi T-50 PAK-FA (officially designated the ‘Su-57’ in December 2017), in February 2018. Hushed-up by Moscow and essentially pointless because hardly any of these had an operational weapons system, the motivation for this enterprise might have been a last-ditch attempt to prevent the ultimate Indian cancellation of further funding for this project, which followed a few weeks later. The examples comfirmed as deployed to Syria were the T-50-10 (Bort ‘510 Blue’) and T-50-11, shown here (RF-81775, first flown only on 5 August 2017!). Although Moscow subsequently released a video showing one of these releasing a guided missile, it seems that neither of the two aircraft fired a single shot in Syria. (Artwork by Tom Cooper)