Operating empty weight

Operating empty weight (OEW) or basic operating weight is the basic weight of an aircraft including the crew, all fluids necessary for operation such as engine oil, engine coolant, water, unusable fuel and all operator items and equipment required for flight but excluding usable fuel and the payload. Also included are certain standard items, personnel, equipment, and supplies necessary for full operations.

The Operating Empty Weight (OEW) is basically the sum of the Manufacturer's empty weight (MEW), Standard Items (SI), and Operator Items (OI).

OEW = MEW + SI + OI

Aircraft purchase price is a near linear function of Operating Empty Weight.

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