This aircraft is MSN 57303506 ex CCCP-26563 Aeroflot before going to Sibir (S7) under registration RA-26563. It was sold to the Sudan Air Force where only 26563 was displayed with no titles, bomb racks equipped,"UN-26563" on wings, all white.....
Full Panel of Experts report here:
http://www.nytimes.com/packages/html...70417SUDAN.doc