Now we know the answer:
Check out this video from Moscow. In the text they claim that it is 2 SU-30 on a mission to bomb ISIS. But the weapons are not for attack! What are they doing?
http://tvzvezda.ru/news/vstrane_i_mire/content/201510041526-7krl.htm
(from http://www.freerepublic.com/focus/news/3344469/posts?page=59#59 )