SAS tried sorting out calamity (8)
I believe the answer is:
disaster
'calamity' is the definition.
('disaster' can be a synonym of 'calamity')
'sas tried sorting out' is the wordplay.
'sorting out' indicates an anagram.
'sas'+'tried'='sastried'
'sastried' is an anagram of 'DISASTER'.
(Other definitions for disaster that I've seen before include "not a success!" , "Event causing great damage" , "Catastrophe, tragedy" , "Great tradegy or cataclysm" , "Sudden catastrophe" .)