Intro
The Bluefin-21 is a large, deep-rated autonomous undersea vehicle developed for demanding subsea missions where deep penetration, long duration, and high-resolution data collection are crucial. With a 53 cm diameter, 4.93 m length, and dry weight of 750 kg, it is built with a free-flooded modular architecture that supports rapid payload and battery reconfiguration in the field.
Its modular design enables integration of multiple advanced sensors simultaneously — such as side-scan sonar, sub-bottom profilers, and multibeam echosounders, giving Bluefin-21 the flexibility to be tailored for oceanographic research, hydrographic mapping, mine countermeasure support, or unexploded ordnance exploration.
Powered by nine 1.5 kWh lithium-polymer pressure-tolerant batteries (13.5 kWh total), the UUV can operate for up to 25 hours at 3 knots with a standard payload, while its gimbaled ducted propulsion offers stable, efficient motion through varied water conditions. Navigation employs a fusion of INS, DVL, SVS, GPS when surfaced, and USBL tracking to achieve real-time positioning with ≤0.1 % dead-reckoning drift accuracy (CEP 50).
Communications are supported via RF, Iridium satellite, and acoustic links, with additional Ethernet connectivity when interfaced through shore power cables. Safety features include fault and leak detection, dropweights, acoustic transponders, strobe lights, and radio direction finders — all independently powered for mission resilience.