The Top End of Australia, particularly around Darwin, is known for its strong car culture. Events like the annual V8 races at Hidden Valley and the World Solar Challenge (a solar car race from Darwin to Adelaide) draw tens of thousands of spectators.

In 1983, a group of friends attempted to drive their Toyota Landcruiser across Darwin’s harbor. Although the friends had to return to shore after 3 km, they still set a world record for the longest underwater car drive.

Now, decades later, another group of Darwin residents has broken the 3 km world record by a wide margin.

On Saturday, July 29, a group of people drove underwater across Darwin’s harbor in an electric-powered Landcruiser named the “Mudcrab.” The Mudcrab is a former diesel car that was converted into an electric vehicle (EV).

The Mudcrab made a remarkable journey through the ocean with the help of divers and engineers. It began at Mandorah and traveled 7 km to land at Mindil Beach. Throughout the 12-hour journey, it overcame challenges like mud, water, and even a gas pipeline.

The Engineering Process

The Mudcrab project holds a special significance for the engineers involved. For engineers Finn Davy and Glen Summers, the project combines adventure and technical challenges in a way that celebrates Darwin’s unique local culture.

Besides engineers, other workers involved in the project included a television production company, commercial divers, skilled mechanics, fabricators, and local tradespeople.

The sourcing EV components proved to be more challenging than expected. There’s only one supplier of electric motors and controllers in all of Australia. After obtaining the motor and controller from a shop in Victoria, the engineers encased the motor, controller, and batteries in silicon oil to ensure waterproofing.

During the development process, the team focused on determining the ability of various components to function in oil and under pressure. They conducted extensive pressure testing, using a specially built chamber to test battery cells and motor control capacitors.

Inspired by techniques used in underwater remotely operated vehicles (ROVs), the team discovered that electrical hardware specifications rarely indicate deep-water, high-pressure compatibility. Consequently, they had to perform their own investigations to ensure component suitability.

The End Result

The Mudcrab had its tires filled with water to withstand the pressure at depths of up to 30 m. Although the car frequently got stuck in mud, the power supply remained steady, allowing it to continue its journey.

Ultimately, the Mudcrab EV conversion is an excellent demonstration of how EVs are not only the most environmentally friendly cars on the market today. They are also the most durable.

Image Source: Supercar Blondie,