Mantis Submersible

Mantis Submersible, c. 1980

The Mantis Submersible is a one-person micro sub designed by British marine engineer Graham Hawkes in 1978, and constructed by Offshore Systems Engineering Ltd (OSEL) in Great Yarmouth.

The Mantis was designed to be lowered into the water from the deck of a larger ship, it would remain connected to its mother vessel via an umbilical tether for safety, being monitored from a control cabin on the ship. Nonetheless, with 10 electric thrusters offering 0.6 horsepower each, and an additional two 2.5 horsepower thrusters, the sub was highly manoeuvrable and could operate across a wide area at depths of up to 700m in all but the stormiest conditions.

The sub was designed for inspecting underwater pipelines and cables, as well as supporting the installation and maintenance of oil rigs and ocean platforms. It features two hydraulically operated manipulator arms for interacting with objects in the water. Innovative for the time, these claws used pressurised seawater as their hydraulic fuel as an alternative to oil. This meant they could be replenished from surrounding water in the event of a leak, and removed the need for additional built-in storage containers. It also removed the risk of environmental damage from a leak. The downside of this technology is that seawater has corrosive properties which would lead to the manipulators requiring additional maintenance in the long-term. Mantis was also capable of being equipped with a range of other tools, including devices such as a submarine rescue drilling machine designed after the KURSK submarine disaster (2000).

With a boarding hatch at the rear of the vessel, Mantis was designed to be operated by a pilot: a trained engineer who could make assessments of any underwater problems encountered on the seabed. The pilot would have high visibility through the submersible’s hemi-spherical dome. However, the submersible could also be equipped to operate as a remote operating vehicle (ROV), controlled from the surface, and is equipped with a camera to allow a video feed to be sent through the umbilical to the control cabin onboard the surface ship. In the event of a disaster, the Mantis has life support for at least 90 hours and all externally fitted equipment is jettisonable; in an extreme case the pilot would be left within a smooth snag-free and very buoyant life support capsule.

This Mantis submersible was used by BUE HMB Ltd, an Aberdeen-based commercial underwater engineering company, from its construction in c.1980 until 1986.

Another Mantis, very like this one, was used in the James Bond film “For Your Eyes Only” (1981). Piloted by its designer, Graham Hawkes, whose character is credited in the film as ‘Mantis Man’. He uses the Matis’s manipulator claws to attack the submersible being piloted by Bond girl Melina Havelock, played by Carole Bouquet, and Roger Moore’s Bond.