PSA Airlines Canadair Regional Jet Systems (PSA-CRJ) Practice Exam

Which of the following results occurs if the engine fire system is functioning properly?

1. Discharge lights illuminate when armed

2. Squibs on fire bottles remain inactive

3. Only fire bottles for the APU operate

4. Fuel valves cannot be closed

The correct answer is: Discharge lights illuminate when armed

The result that occurs when the engine fire system is functioning properly is that discharge lights illuminate when armed. This is a critical safety feature of the fire suppression system. When the system is armed, the illumination of the discharge lights indicates that the fire bottles are ready to be activated in the event of a fire. The presence of illuminated lights serves as a visual confirmation for the crew that the fire suppression system is operational and prepared to discharge extinguishing agents if a fire is detected. This functionality is essential for ensuring the safety of both the aircraft and its occupants in case of an engine or APU fire. In contrast, the other options pertain to scenarios that would not indicate a properly functioning system. For example, if squibs remain inactive, it may suggest an issue with the fire suppression system, indicating that the fire bottles are not ready to discharge. Similarly, if only fire bottles for the APU were operating, it would imply that the system is not functioning as intended for the engines. Lastly, if fuel valves were unable to be closed, it would point to a malfunction that could exacerbate a fire situation, contradicting the expected performance of a functioning fire system.