The Control of Atmospheric Pollution from Gas Turbine Engines 680347
The main forms of atmospheric pollution by gas turbine exhaust are smoke and oxides of nitrogen at top speed and unburned fuel and carbon monoxide at engine idle conditions. Smoke trails constitute a visual nuisance and the other contaminants are either toxic or irritant or both.
Combustor design with improvements in fuel air mixing and the use of air assisted sprayers will reduce smoke to barely visible levels on future engines. In addition, the latest annular chambers will give reduced concentrations of unburned fuel and carbon monoxide.
Oxides of nitrogen will be difficult to reduce but current concentrations are less than measured on the automobile.