Russian Air Force officials expect the investigation into the crash to last up to 30 days. Flights have been suspended until the conclusion of the investigation.
Russia built the SU-27 to compete with America's F-15. About 450 SU-27 Flankers make up the Russian fleet while another 200 have been shipped to Russian allies such as China. There have been no reports of other countries grounding their SU-27 fleets.
Investigators have recovered the flight recorders. Officials told Moscow Times the crash was likely caused by pilot error or technical problems with the onboard flight system. There's also the possibility the crash was caused by a bird.
Considering Russia's flagging defense budget, the military can't afford to lose fourth generation fighters in training runs. Despite the lack of air-to-air combat, the world's fighter aircraft have experienced a string of problems. The U.S. Air Force is still trying to figure out why the F-22 fighter jet keeps suffocating its pilots.
Thursday's crash coincidentally occurred near where a Tu-134 airliner crashed that killed 47 people. That investigation later found the pilot was drunk.