Performance tests were conducted for an air ejector entraining two secondary jets whose axes are coaxial of that of primary stream. A unique ejector housing was constructed to receive both the convergent or convergent-divergent primary nozzle and the cylindrical mixing chamber. The air ejector under investigation has nozzle throat -tocylindrical section area ratio of 0.12. The investigation is conducted for ejector having cylindrical length-to-diameter ratio, which varies from 2.31 to 23.08. It covers a range of spacing from –1 to 0.5 of cylindrical lengths and of secondary to ambient pressure ratio of 1.0. The recorded axial distributions of the static wall pressure are plotted in nondimensional forms and the extent of consistency of the profiles is shown. The induced air flow rate ratio is plotted for the measured primary to secondary stagnation pressure ratio range. Results offered a valuable appreciation of the effect of the cylindrical length and nozzle spacing-todiameter ratios on both wall pressure distribution and jet entrainment capacity. The occurrence of flow choking in both the convergent or convergent-divergent primary nozzle was ensured.