South Sudan is one of the youngest countries. Offcially it became formally independent on 9 July 2011 after a six year long periode of uncertainty after the peace traty with Sudan. It has become a UN member state too.
Interestingly, the air force received its first hardware late 2010 when the first Mi-17 helicopters arrived at Juba! After the sole Beech 1900 was sold, only helicopters remain in the air force fleet as of 2015. All should be based at Juba airport.