Abstract: A compressor inlet housing includes a bleed heat duct assembly that is disposed within the compressor inlet housing. The bleed heat duct assembly includes a duct having a plurality of walls defining an opening and a slot defined along a wall of the plurality of walls. The bleed heat duct further includes a bleed air manifold and a plurality of feed pipe assemblies that is disposed at least partially within the opening and that is in fluid communication with the bleed air manifold. Each feed pipe assembly of the plurality of feed pipe assemblies includes an inner pipe having an upstream end connected to the bleed air manifold, a cap sealingly connected to a downstream end of the inner pipe and a pin that extends outwardly from the cap. The pin extends into the slot.

Abstract: The present disclosure is directed to a sound attenuation system for a gas turbine engine. The sound attenuation system includes a compressor inlet casing having a compressor inlet casing inner surface and defining a compressor inlet passage extending therethrough. An inlet plenum body couples to the compressor inlet casing. The inlet plenum body includes an inlet body inner surface and defines an inlet plenum therein. One or more sound attenuating panels couple to at least one of the compressor inlet casing inner surface and the inlet plenum body inner surface of the duct. Each sound attenuating panel includes a first sheet defining a first plurality of apertures extending therethrough and a solid second sheet spaced apart from the first sheet.