Try failure, fall, fell stroke, fiasco, or flop.
Fiasco
a synonym for crisis: disaster.
A synonym for tender beginning with 'a' is affectionate.
catastrophe?
Disaster
shock
One option is the word disaster.
Disaster
A synonym starting with d of the word calamity is 'disaster'
"Disaster" is probably the closest synonym, but "distress" rather close.
A disaster, like a calamity is a hugely problematic turn of events.
tragedy, disaster, collapse, downfall, cataclysm
disaster