Manned-unmanned teaming is a key aspect for improving the efficiency of civil and military operations. This paper provides an overview of a four-year project to develop and evaluate methods for manned-unmanned teaming formation flight. The formation flight scenarios are tailored towards manned and unmanned rotorcraft performing a close formation flight. This paper explains use cases as well as the test methodology. Two formation flight algorithms were developed and evaluated against a preprogrammed waypoint-based baseline. The evaluation was done in a simulator campaign with different pilots and in a flight test campaign with one evaluation pilot. During the final flight test campaign the first coupled close formation flight between a manned and an unmanned helicopter was achieved. Finally, this paper contains the results of both the flight test and simulator campaign.