You'll see his aircraft, a machine for making screws, hydraulic timber-cutter, revolving bridge, various machine-tools, and a system of map-?­making by aerial views created long before any aircraft, even his, was operational.
His aircraft is still operational to this day.  
mnli hypothesis: His aircraft is still operational to this day.   premise: You'll see his aircraft, a machine for making screws, hydraulic timber-cutter, revolving bridge, various machine-tools, and a system of map-?­making by aerial views created long before any aircraft, even his, was operational.