The performance of combustion driven cw HF chemical lasers using the HYpersonic Low- TEmperature (HYLTE) nozzle at the fundamental (2.8 micrometers ) and overtone (1.3 micrometers ) wavelengths was investigated. A pseudo-two dimensional, rotational equilibrium, finite rate, chemical kinetic, mixing laser simulation code, Blaze II, was used to model the HYLTE nozzle. The fluid dynamic profiles from Blaze II were used as input to the computationally efficient, rotational nonequilibrium model, ORNECL, which was used for power and small signal gain (SSG) calculations. The Blaze II fluid dynamic profiles and the ORNECL SSG profiles compared very well to the Direct Simulation Monte Carlo (DSMC) calculations performed by TRW. ORNECL was used to calculate the fundamental and overtone powers and SSG's for various flow conditions. Good agreement with experimental data was obtained. Calculated powers, SSG's and power spectral distributions (PSD's) are reported. The ORNECL model, which was baselined to experimental data, can be used to predict the performance of the HYLTE nozzle in advanced gain generator configurations. Blaze II and ORNECL (capable of power and SSG calculations) provide an inexpensive simulation of the HYLTE nozzle.