TODO: Figure B.23: The sense of direction seems the wrong way round in the Block flow properties and FlowSpecification | Dr Darren's MagicDraw UML and SysML Plugin eSchool

Compare the sense of Fuel flow direction in:

Figure B.19 - Internal Structure of the Power Subsystem (Alternative 1 - Combined Motor Generator)
Figure B.25 - Detailed Internal Structure of Fuel Delivery Subsystem (Fuel Distribution Detail)

The flow of Fuel "supply" is from ft:FuelTankAssembly to the ice:InternalCombustionEngine, and the sense of Fuel "return" is from the engine to the tank. However in the original SysML1.0 sample Figure B.23 - Elaborating Definition of Fuel Flow. (Block Definition Diagram) the FlowProperty fuelSupply:Fuel is 'in' on ft:FuelTankAssembly and 'out' on ice:InternalCombustionEngine. Also, flow properties of the FlowSpecificationFuelFlow (if not conjugated at the engine) would then have to be fuelSupply:Fuel 'out' & fuelReturn:Fuel 'in'.