In the present study, the flame length in a coaxial diffuion flame configurations was investigated by varying the Jet A1 fuel flow rate, temperature of the oxidizer stream, and inert gas concentrations in the oxidizer stream. Experimental results clearly showed that the measured flame lengths are proportional to the Jet A1 fuel flow rate as well as increases in the temperature of the oxidizer stream and increases in the inert gas concentration in the oxidizer stream results in stretching the flame. Inert substitutions in the oxidizer stream was found to be one of important mechanism to affect the flame length.