The fifth enlisted rank of the Weltraumflotte and the second NCO rank. In this position, many Hauptbootsmann are the senior departmental NCO. However, two Hauptbootsmann per shift with the best performance ratings among their peers are often placed under the vessel's Stabbootsmann as his “Bosun's Mates” and act as the Bosun's Assistants. This is normally a honor considering they have to be the best of the best.

In the Weltraumflotte Marine Corp, a Hauptbootsman is normally a Platoon's Senior NCO.