BLEED AIR OFFTAKE ASSEMBLY FOR A GAS TURBINE ENGINE

A gas turbine engine (10A; 10B; 10C) comprising: a duct (30) extending about an axis (C), the duct (30) including an outer-duct wall (32) having an interior-duct surface (32i) circumscribing an interior of the duct (30) and an exterior-duct surface (32e) radially outward of the interior-duct surface (32i) relative to the axis (C), the outer-duct wall (32) defining an offtake opening (34) extending from the interior-duct surface (32i) to the exterior-duct surface (32e), the offtake opening (34) in fluid communication between an offtake location (L1) inside the duct (30) and outside the duct (30); and a bleed air offtake assembly (40) including: an air line (60) in fluid communication with inside the duct (30) via the offtake opening (34), the air line (60) having a first-line end defining a line inlet (62) proximate to the outer-duct wall (32) and a second-line end spaced from the first-line end; a valve (70) located outside the duct (30) and fluidly connected to the air line (60) via the second-line end, and a conduit (80) having a conduit inlet (82) in fluid communication with inside the air line (60) at a resonance location (L2) between the first-line end and the second-line end upstream of the valve (70), and a conduit outlet (84) in fluid communication with inside the duct (30) at a relief location (L3) spaced from the offtake location (L1).