User interfaces for the command and control of transportation and navigation systems, such as aircraft cockpits, usually integrate several types of interaction elements: physical, hardware or software. Within these cyber-physical environments, operators have to complete their tasks manipulating these different types of elements. However, task description notations do not take into account physical and hardware aspects beyond manipulation of input devices such as mouse and keyboard. This paper identifies generic aspects of cyber-physical interactive systems and proposes extensions to operators' tasks description techniques, to capture them. We argue that representing cyber-physical elements explicitly and systematically in task models contribute to the design and development of usable and reliable transportation systems. These extensions are integrated within the tool-supported notation called HAMSTERS and are illustrated on a case study from the avionics domain.