Despite the development of the technology required to support single pilot operations (SPO) in civil aviation, the definition of roles of the single pilot and the diffusion of responsibilities between the human and the autonomous system are still under study. In this paper, we propose a critical analysis of existing SPO concepts involving a highly autonomous teammate in the cockpit. We show that not all facets of responsibility are addressed. In an attempt to solve this issue, we propose to extend a framework to support the analysis of authority, responsibilities, resources shared between roles and permissible control transitions when designing collaboration with autonomous systems.