Flag Germany The Greyshark Series 2 AUVs (autonomous underwater vehicles) developed by Fassmer Defence in Germany have distinctive biologically inspired hull forms to maximise efficiency. Although named after a shark, the animal form appears closer to a penguin. This gives the craft an impressive cruising speed of 10 knots, a maximum speed of more than 12 knots, and strong agility.

Greyshark AUV

Another unusual feature is that the screw (propeller) is mounted on a large, segmented ring around the outside of the hull and ahead of the simple X-form control surfaces at the stern. On early prototypes this screw had a large shroud, but this has since been removed, although fixed stators remain just ahead of the screw.

The Greyshark comes in two variants, the battery powered Bravo and the fuel cell AIP (air-independent power) Foxtrot. The two designs share the same profile and length-beam ratios, but the Foxtrot is larger. Both versions, however, can be road transported in a standard ISO 40 ft shipping container.

Specifications – Greyshark Bravo
Length: 6.5 meters
Beam: 1.75 meters
Weight: 3.5 tonnes
Speed: 10 knots, 12+ knots maximum
Powerplant: Battery-electric
Range: 60 nautical miles @ 10 knots, 550 nautical miles @ 4 knots

Specifications – Greyshark Foxtrot
Length: 7.99 meters
Beam: 1.8 meters
Weight: 5 tonnes
Speed: 10 knots, 12+ knots maximum
Powerplant: fuel cell AIP -electric
Range: 1,100 nautical miles @ 10 knots, 8,000 nautical miles @ 4 knots

Greyshark AUV

Greyshark Bravo at DWT Marineworkshop exhibition in Linstow, Germany, September 2025. Thank you to the photographer!

Roles are primarily advertised for ISR (intelligence, surveillance and reconnaissance), and protection of offshore undersea infrastructure. With critical national infrastructure in focus in Europe this appears particularly relevant.

The battery version has a range of over 500 nautical miles (1,000 km) at slow speed, while the AIP version is expected to achieve 8,000 nautical miles (16,000 km) at the same speed. Combined with the ability to carry external payloads, conceivably mines or torpedoes, this makes it a promising European AUV design.

Greyshark AUV

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