German shipbuilder TKMS (Thyssenkrupp Marine Systems) is beginning to build a prototype of the civilian Modifiable Underwater Mothership (MUM) uncrewed underwater vehicle (UUV) with assembly expected to begin in the summer.
At 25 meters (82 feet), the TKMS system will be slightly longer than other military XLUUVs being developed in the United States, United Kingdom, China, and Australia, but, most importantly, it will be twice as wide as any publicly known designs, according to naval reporting and analyst HI Sutton writing for Naval News in February. The MUM will employ a “flat fish” design that will increase its stability while surfaced, which is important given that in its civilian role it is expected to spend time either deeply submerged or on the surface rather than at periscope depth.
TKMS’ MUM product page stresses its multi-mission capability and innovative design concept that is “composed of almost freely configurable base and mission modules, enclosed by a hydrodynamic casing.” The base and mission modules “are designed as ten- or twenty-foot standard containers, making their transportation and assembly effortless. The combination of base and mission modules enables MUM to fulfil different types of missions as well as to scale its capabilities in endurance or payload capacity.”
According to Sutton, the MUM is envisioned to carry out several civilian roles such as inspection, maintenance and repair, and exploration of offshore oil and gas fields or marine mineral deposits, potentially taking samples via drill or support seismic surveying. Nonetheless, military variants of MUM XLUUV for minelaying, hunter-killer operations, and the scout / intelligence collection role have been discussed and even advertised by TKMS.