What happens when the fuel level in the collector tank reaches approximately 40 lbs?

The correct answer is that fuel flow may become limited when the fuel level in the collector tank reaches approximately 40 lbs. This situation typically indicates that the fuel level is becoming too low for optimal operation. At this threshold, systems are designed to ensure reliability and safety by restricting the amount of fuel available for use. This limitation prevents potential operational issues that could arise from insufficient fuel supply, allowing time for maintenance personnel to address the fuel level before it becomes critical.

In this case, while an alarm could signal a low fuel level or there may be an option for emergency fuel, these features do not directly address the operational effects and limitations on fuel flow. The tank automatically refilling might occur under different operational conditions but is not the primary concern when the fuel level reaches this specific amount. Thus, focusing on the limitation of fuel flow accurately reflects the intended design and operational parameters of the system at that threshold.