EFOB meaning in aviation

Where this term is used / What it means in practice

EFOB appears in dispatch systems, flight planning tools, FMS predictions, and in-flight fuel monitoring. It is a projected figure, not the measured fuel quantity at the present moment. Crews and operational control use it to judge whether the flight remains inside the fuel plan and whether the destination, alternate, diversion, or holding strategy remains acceptable.

In practice, EFOB is a decision support figure. A predicted EFOB at destination, alternate, or fuel decision point helps the crew compare the plan with actual performance. If the prediction trends down, the crew may need a new routing, lower-level operational action, or a diversion decision before the fuel state reaches a formal threshold.

What EASA says

The current EASA air operations framework for aeroplane fuel planning and in-flight fuel management is structured around the fuel/energy scheme, including planning policy and in-flight management policy. The operator must establish procedures to plan sufficient usable fuel and to monitor and manage the flight as conditions change. EFOB is one of the operational figures used inside that controlled process.

Common confusion / Common mistakes

The main confusion is EFOB versus FOB. FOB is the fuel currently on board. EFOB is what the system predicts will remain later. They are related but not interchangeable.

Another common mistake is using a comfortable EFOB prediction as if it were guaranteed. It is a forecast derived from assumptions about route, wind, level, temperature, and configuration. It must be rechecked as the flight develops.