The use of drones in the maritime sector has not been extensively explored yet. A collaborative project between the German Federal Police and the German Aerospace Center is investigating the potential use of a drone launched from a patrol boat. This prompts the following question: Which human factors are key for safe drone operations while efficiently accomplishing the mission objectives? To answer this question, we conducted literature research and analyzed twelve relevant studies. A total of twenty factors were identified. The five most frequently mentioned factors relate to situational awareness, judgment/decision-making, communication, teamwork, and manual flying skills. The relevance of each human factor for successful deployment is explained and analyzed in detail. The results of this study may serve as a foundation for the incorporation of human factors into a training concept for future maritime drone crews.