2. Boeing Echo Voyager

One monument to autonomous underwater endurance is Boeing’s Echo Voyager. Driven by a hybrid rechargeable power system, this 51-foot-long boat can run months without surface support. Its amazing 8 tonnes payload capacity allows it to carry research tools and advanced sensor arrays. The Echo Voyager uses cutting-edge autonomous navigation systems and a special autonomous charging system to surface regularly and run diesel generators, therefore replenishing its batteries. Its strong communication package guarantees continuous connection with operation centres by including underwater acoustic messaging and satellite uplink capabilities.