Abstract: A combustor for use in a gas turbine engine is provided with a first wall defining a combustion zone; an outer casing partially defining a cooling plenum about the first wall; a second wall spaced apart from the first wall and defining together therewith a second plenum, the second wall bearing a plurality of perforations for passing fluid from the first plenum in impinging streams upon the first wall; and a plurality of ribs extending between the first and second walls and compartmentalizing the second plenum. The ribs add substantial stiffness to the combustor as well as providing for independently controlled cooling of the substantially isolated compartments formed thereby. The impinging streams provided by the perforations in the second wall substantially increase local fluid velocities and conductive heat transfer.