The fire severely damaged the stage area.  Likely started by vandals, the flames would have caused far more destruction had it not been contained by the old fire curtain, which worked just as it had been designed to do, dropping at the front of the stage and preventing the blaze from burning further into the auditorium.  

Sources:

“Suspicious Fire Hits City’s Once-Famed Carolina Theatre,” Charlotte Observer, November 14, 1980.

“Old Fire Curtain Saved Carolina Theatre from Ruin,” Charlotte News, November 14, 1980.

“Fire Guts Carolina Theatre,” Charlotte News, November 13, 1980.