Biplane in Flight

I believe this is a Sopwith Camel. The photo is from October, 1975 - one of the eclectic slides from Lot 1....

Sopwith Camel

Another view of the biplane first shown here....

View From the Tarmac

The white plane in this photo is eluding my best efforts at identification. It is not a Harbin Y-12, not a de Haviland Dash 7, not an Ilyushin. Any ideas?...