What does the DUCT TEMP light indicate?

The DUCT TEMP light serves a vital function in monitoring the temperature of the air within the aircraft's ducting system. When this indicator is illuminated, it signifies that the temperature of the air in the ducts has exceeded a threshold of 300°F. This is a critical safety feature, as excessively high air temperatures can lead to system failures, affecting both performance and safety.

Understanding this indicator is crucial for pilots and crew, as it requires immediate attention to avoid potential overheating issues. Monitoring the environmental conditions within the aircraft ensures that operational standards are maintained and helps prevent damage to equipment or hazardous conditions for those on board.

Other options do not accurately describe the function of the DUCT TEMP light. For instance, while air duct blockage could lead to increased temperatures, it is not what the light directly indicates. A system malfunction could cause various warning lights to illuminate, but the DUCT TEMP light specifically relates to temperature thresholds. Additionally, low air pressure would generally be indicated by a different set of warning indicators and does not correlate with the temperature alert. Thus, the correct interpretation of the DUCT TEMP light is that it signals when duct air temperature has surpassed the critical level of 300°F.