Reports of a civilian passenger aircraft being shot down over east Ukraine are, if true, deeply worrying. Details are currently very scanty and it is unclear what or who might have been responsible for the crash.
At normal cruising altitude a civilian passenger aircraft would be out of the range of the sort of manned portable air defence systems that we have seen proliferate in rebel hands in east Ukraine. However, it would be in the range of medium-altitude (and above) surface-to- air missile systems such as the 9K37 Buk (SA-11 'Gadfly') or the S-300 (SA-10 ‘Grumble), or later versions of either. Both Russia and Ukraine have such SAM systems in their inventories.