The Russian Air Force grounded all its MiG-29s following a crash in Siberia on 17 October 2008. Following a second crash with a MiG-29 in east Siberia in December 2008, Russian officials admitted that most MiG-29 fighters in the Russian Air Force were incapable of performing combat duties due to poor maintenance. The age of the aircraft was also an important factor as about 70% of the MiGs were considered to be too old to take to the skies. The Russian MiG-29s have not received updates since the collapse of the Soviet Union. On 4 February 2009, the Russian Air Force resumed flights with the MiG-29. However, in March 2009, 91 MiG-29s of the Russian Air Force required repair after inspections due to corrosion; approximately 100 MiGs were cleared to continue flying at the time. The Russian Air Force started an update of its early MiG-29s to the more current MiG-29SMT standard, but financial difficulties prevented delivery of more than three MiG-29 SMT upgrade to the Russian Air Force. Instead, the 35 MiG-29SMT/UBTs rejected by Algeria were bought by the Russian Air Force. Russia placed an order for 16 new-build MiG-29SMTs on 15 April 2014, with delivery expected by 2017.