Zero-Fuel Weight (ZFW)
Zero-Fuel Weight (ZFW) is the total aircraft weight without usable fuel. It includes the aircraft's structure, payload (passengers, cargo), and crew. ZFW is critical for calculating maximum takeoff weight and fuel load, ensuring the aircraft operates safely within structural and performance limits.
Definition
Zero-Fuel Weight (ZFW) refers to the weight of the aircraft and all contents onboard, excluding usable fuel. It represents the sum of the aircraft’s basic operating weight plus payload (passengers, baggage, and cargo).
Importance
- ZFW is critical for calculating the maximum amount of fuel that can be loaded without exceeding the Maximum Takeoff Weight (MTOW).
- Ensuring ZFW is within structural limits preserves the integrity of the airframe, especially wing bending relief.
- It provides a baseline for performance planning, affecting center of gravity and flight efficiency.
Calculation
ZFW = Operating Empty Weight (OEW) + Payload
- Operating Empty Weight (OEW): Includes the aircraft structure, unusable fuel, required fluids, and basic equipment.
- Payload: Includes all passengers, baggage, cargo, and other load items.
Regulatory Considerations
The Maximum Zero-Fuel Weight (MZFW) is a certified limitation specifying the highest permissible ZFW. Exceeding the MZFW can overstress the wings and structure because the wings rely on fuel weight for bending relief during flight.
Operational Implications
- Properly managing ZFW ensures wing loading stays within safe limits.
- Accurate ZFW calculation helps in determining fuel requirements and ensures optimal performance.