To make short : Su-20 was the export name of Soviet Su-17M with Lyulka AL-21F engine. Subsequent models of Soviet Su-17, like Su-17M2, M3 and M4 (with associated twin-seat UM) were exported, at the request of customers, with Tumansky R-29B engines, as Su-22M2, M3 and M4 (With K as other distinctions for electronic downgrades).

Some kind of humanitarian program, not sure yet.

Early Angolan Fitters:
[ATTACH=CONFIG]239260[/ATTACH] [ATTACH=CONFIG]239261[/ATTACH]

Thanks.
And thanks for Su-22M-2K pictures (especially the one with Recce pod). I didn’t know they received this variant.

Old Sudanese AF Provost :

Brazil again :