She arrived in Halifax, Nova Scotia, on Sunday 5th June, [2022].”  The ship is the largest autonomous vessel to have made this voyage. The original plan was to commemorate its namesake’s 1620 landing in Plymouth, Mass., but that plan ironically recreated the path of the historic event by having to turn back to port on its first attempt last year. In June 2021, the MAS 400 returned to Plymouth, England, due to mechanical problems, as had the Mayflower in 1620. The original sailing had leaks aboard Mayflower’s sister ship the Speedwell.

A look at the two Mayflowers offers an interesting measure of the progress made by technology.


Mayflower built in 1609

  • Class: Dutch cargo fluyt, triple-masted, four decks, 180 tons, 110-feet overall
  • Wind-powered
  • 102 passengers and about 30 crew members
  • Top speed three knots (6km/h)
  • Crossed the Atlantic—10 weeks at sea


Autonomous Mayflower built 2020-21

  • Class: Autonomous trimaran, triple-hulled vessel, five tons, 50-feet overall
  • Solar-powered with IBM AI, automation, and edge technologies
  • No passengers or personnel (“AI Captain”)
  • Top speed 10 knots (20km/h)
  • Crossed the Atlantic—40 days at sea

If it seems unusual that the speed advantage of the more recent Mayflower has only tripled in the last 400 years, that was by design. Although trimarans are more stable and faster than traditional catamarans (two-hulled sailing ships), the MAS 400 didn’t need this advantage. The builders explained that when you don’t have any people aboard, there’s no need to rush. And more importantly, the ship is designed for marine research. Collecting data is what it does, not rush passengers or cargo from place to place.


Jonathan Batty, the chief communications officer for the Mayflower Autonomous Ship project points to the 700 kg. (1,543 lbs.) of equipment in three payload bays to explain the scientific mission. A complete acoustic array for sound, water and air samplers, nutrient samplers, sonar, depth sensors, and more are there to “taste the ocean” and listen to the whales and other marine mammals in very remote places.

Most of the planet is covered by water, and 80% of the world’s oceans remain unexplored. What’s needed now, Batty explains, are more flexible and cost-effective ways of gathering data about this part of the environment that’s responsible for trillions each year in economic value and that also moderates the Earth’s temperature and produces more than half of the Earth’s oxygen from oceanic plankton. One particular type of these floating plants, Prochlorococcus, is the smallest organism on Earth sustaining itself through photosynthesis. According to the U.S. National Oceanic and Atmospheric Administration (NOAA) ocean service, “This little bacteria produces up to 20% of the oxygen in our entire biosphere. That’s a higher percentage than all of the tropical rainforests on land combined.”

To build an autonomous ship to collect data, the planners needed to develop an “AI Captain.” Batty describes this agent as a fusion of data that can sense, think, and make decisions at sea, using six on-board video cameras and an array of other sensing devices to provide automated decision making with limited connectivity.

The research fields selected for data collection and scientific study include: water-quality testing, pollution sampling, chemical evaluation, sea levels, intelligent navigation, whale songs, and the environment in general. An historic goal for the project chose the 400th anniversary of Mayflower voyage to connect the past and the future of oceanic exploration. The plan was to duplicate the voyage from the Plymouth port on the English coast to Plymouth, Mass. The successful crossing, just completed in June 2022, included a diversion at the end of the voyage to Halifax, Nova Scotia, due to a malfunctioning of the backup generator for the solar cells.

Nevertheless, the Atlantic had been crossed again, only this time by a crewless vessel. In the judgment of Brett Phaneuf, cofounder of the marine research organization, ProMare, “The single biggest challenge is the ocean itself. No ship has ever been built that can survive whatever the ocean could throw at it.”



The Mayflower 400 was built by a global coalition of partners including shipbuilders, computer techs, and marine scientists. The owners are the two primary partners IBM ( and the nonprofit fundraiser ProMare ( dedicated to marine research and exploration. Four companies collaborated on the design and construction, and Thales and Iridium served as official communications partners. Twenty-seven other companies provided equipment and services, and 15 organizations were research partners. These included six universities, the Plymouth Marine Laboratory, and NOAA.

The original Mayflower was launched on her maiden voyage in 1609, and she reached the end of her usefulness around 1624 when the owners most likely gave her over to England’s Rotherhithe district shipbreakers. The longevity for the MAS 400 will depend on the quality and usefulness of the data collected in otherwise unexplored seas. Most likely, her aluminum hulls will be searching the seas around the world for more than the decade and a half of its historic namesake.

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