Museum of Yugoslav Aviation at the Belgrade Nikola Tesla Airport (BEG) looks very interesting. Larger planes seen here are Sud Aviation Caravelle, Iljushin IL-14, Junkers Ju 52 and Douglas DC-3. There are also group of Mig-21's, a Mig-23 and many Jugoslav-built Soko Galeb jet trainers. Inside the museum there are the remains of F-117 82-806 shot down on March 28, 1999, near Budjanovci, Serbia. Info link has many fine photographs of the exhibits.
(Museum of the Yugoslav Air Force)
http://www.muzejrv.mod.gov.rs/pages_files/istorijat_files/istorija.html