http://www.hitechweb.genezis.eu/transport5.htm
http://www.twitt.org/bldwing.htm
http://en.wikipedia.org/wiki/Operating_empty_weight
Operating empty weight (OEW) 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.
