The main role for the Canadian Armed Forces starts with requirements definition. A capability is required, and then we drift into what the actual detailed requirements are for that capability. In this case, we're talking about the replacement for the CP-140, so that's everything from the range of the aircraft to what it needs to be able to do from an anti-submarine warfare and anti-surface warfare perspective, which means the defensive mechanisms it needs, the missiles it needs to carry and the threats it needs to mitigate.
The armed forces start there, and as the requirements get further defined and we transition into a procurement process and procurement planning, my colleagues at PSPC get more heavily involved, but even throughout that process, the armed forces would play a role in clarifying requirements, maybe validating the information that comes back against their requirements to make sure it does indeed meet them.