Wall deflections of a multi-lobe type noise suppressing nozzle are minimized without the use of external struts and by the use of only a single internal strut per lobe. The lobes have either a substantially elliptical or substantially circular shape in cross section and they merge into valley regions of substantially circular curvature in cross section. The internal struts and thickened sidewall portions of the lobes define a structural ring providing hoop and bending strength at the center of the nozzle. The thickened sidewall sections of the lobes are welded to shaped sheet metal crown and forward valley sections to form the nozzle. Wall portions of the nozzle are thinned by the chemical milling for the purpose of weight reduction.