In calculation we consider maximum takeoff weight , maximum landing weight and maximum zero fuel weight
we selected the lowest of below mentioned
- Maximum Zero fuel weight + Take off fuel
- Regulated take off mass
- Regulated Landing mass + Trip fuel
"2" and "3" are related to structural limitations that if we cross we might damage the aircraft or runway while doing landing or takeoff . My understanding is since both Regulated take off weight and Maximum Zero fuel weight is related to structural limitation during take off so Maximum Zero fuel weight would be factor while calculating the Regulated take off weight itself. Then why does we consider Maximum Zero fuel weight separately while calculating take off mass?