An experimental investigation was made of the operational characteristics of a self-contained supersonic cw chemical HF laser. A three-jet nozzle array with reagent jets separated spatially by helium jets was used. This nozzle array (replacing its two-jet analogue) made it possible to increase by a factor of 1.20-1.35 the energy characteristics of the laser and by a factor of 1.4-1.7 (up to 125-150 mm) the length of the active medium, and at the same time reduce by 30 % the level of optical inhomogeneities in this medium.