A hydrogen fluoride chemical laser has been constructed with high‐voltage pulse initiation in a simple transverse discharge geometry. The system delivers a maximum pulse energy of 11 J with about 100‐nsec half‐width. This corresponds to an efficiency of nearly 4&percent; with respect to the electrical input into the pulse generator. An investigation of the voltage and the current flow across the discharge chamber, however, indicates that the efficiency with regard to the actual energy deposition in the gaseous discharge is considerably higher. The discharge parameters for optimum operation are discussed.