ENGINE AND ENGINE INLET ANTI-ICE SYSTEM

TM 1-1520-238-10 2-24 Change 2 FRONT M01-012-1 ALTERNATOR OIL FILTER BYPASS SENSOR OIL FILTER IMPENDING BYPASS BUTTON OIL PRESSURE CHIP DETECTOR FUEL PUMP FUEL FILTER SWIRL VANES OIL DRAIN PLUG SENSOR Figure 2-16 T700-GE-701 / T700-GE-701C Engine (Sheet 2 of 2) 2.25 ENGINE AND ENGINE INLET ANTI-ICE SYSTEM. CAUTION To prevent damage to engines, the en- gine anti-ice system shall be activated when the aircraft is flown in visible mois- ture and the outside air temperature (OAT) is less than +5 C (+41 F). The engine anti-ice system includes the engine inlet fair- ings, and the nose gearbox fairings. Engine fifth stage bleed air is used to heat the swirl vanes, nose splitter, and engine inlet guide vanes of each engine. The nose gear- box fairing is an electrically heated fairing to prevent the formation of ice on each engine nose gearbox fairing. 2.25.1 Engine and Engine Inlet Anti-Ice Opera- tion. The engine anti-ice system is controlled by a two- position ON/OFF toggle switch located on the pilot ANTI ICE panel (fig 2-17). When the switch is placed to the ON position, the ENG 1 ANTI ICE and ENG 2 ANTI ICE advi- sory lights will illuminate and remain on during normal op- eration of the system. The ENG 1 ANTI ICE and ENG 2 ANTI ICE fail lights on the pilots caution/warning panel and the ENG ANTI ICE fail light on the CPG’s caution/ warning panel will illuminate until the nose gearbox fairing electrical heaters reach 205 �F and the temperature sen- sors within the engine inlets reach 150 �F. The time re- quired to reach these temperatures will vary with OAT. When the nose gearbox fairings and the bleed air heated engine inlet reach operating temperatures, the caution/ warning lights will extinguish. When the engine anti-ice system is turned off, the ANTI ICE panel advisory lights will extinguish and the caution/warning ENG ANTI ICE fail lights will illuminate and remain on until the engine inlet temperature sensors cool below 150 �F. The amount of time required for sensors to cool is dependent on OAT and the length of time the engine anti-ice system has been op- erating. The ENG ANTI ICE fail lights may remain illumi- nated for several minutes after the switch is placed in the OFF position. When the switch is OFF, the advisory lights on the pilot ANTI ICE panel indicate when the engine bleed-air valves are open. These lights will illuminate when engine speed is below 91% N_G (bleed valve open) and will extinguish when engine is above 91% N_G (bleed valve closed). When the switch is ON, the advisory lights will