Abstract: An improved system provides cooling air to the turbine blades of a gas turbine engine. The improved system includes the combination of an inducer to receive pressurized cooling air from the compressor and then to direct this cooling air in a substantially tangential direction to a radial flow impeller which includes an air seal. Cooling air is directed to the turbine blades which are mounted on the rim of the rotating first turbine disk. In a preferred embodiment of the invention, a second portion of the cooling air from the inducer is conveyed through a deswirler to introduce the cooling air into a circumferential channel surrounding the rotor shaft. The cooling air is then directed to a second inducer means which is mounted on the higher pressure turbine disk. The cooling air is then directed to a second annular impeller mounted on the lower pressure turbine disk to convey this portion of cooling air to the lower pressure turbine rotor blades.

Abstract: A band clamp apparatus having two 180.degree. segments which are bolted together at flanges on the horizontal centerline. A substantial portion of each segment has a scalloped band contour for weight reduction. An internal groove in the band clamp which has parallel facing walls which engage the mated flanges of the casings of the engine/exhaust system. Local radial restraints are provided on the engine/exhaust system casings to achieve radial constraint and circumferential positioning of the band clamp apparatus.