For what reason do aircraft crews monitor fuel temperatures?

Monitoring fuel temperatures is essential for several reasons related to safety and operational efficiency. One primary concern is the risk of fuel freezing at high altitudes or in very cold conditions. Jet fuel, particularly Jet A, has a freeze point that can lead to the formation of crystal structures within the fuel that could obstruct fuel lines and filters, creating potential operational hazards. By keeping track of fuel temperatures, aircraft crews can ensure that the fuel remains within safe temperature ranges, thus mitigating risks associated with reduced fuel flow or engine malfunction caused by frozen fuel.

Although fuel efficiency, quality, and engine performance are all important aspects of fuel management, the most critical concern emphasizes the safety of the aircraft operations by preventing hazards that could arise from improper fuel temperatures. Monitoring ensures that fuel remains usable and does not introduce any danger during flight operations.