Angola fly B747-300 mostly out of JNB
D2TEA and D2TEB
The crew seem ok from an ATC point of view not realy that different from other african airline crew, However sometimes they bly a B737-200 and that crew is totally disasterous. But they havn't flown for a long time that I know of.
The umbo's I think are maintained by SAA cause they seem to get towed to the SAA Technical area about once a month or so for the day. But thy could also be going there for a wash only.