Modeling software used to seek sunken war ship

22.11.2006
Custom-built computer-based modeling software from Applied Science Associates (ASA) is being used to help locate the long-lost underwater wreckage of the ship used by Capt. John Paul Jones during the Revolutionary War in 1779.

The Bonhomme Richard, on which Jones declared "I have not yet begun to fight," is believed to lie 150 to 200 feet below the surface of the North Sea. An expedition to find the wreckage began last summer with a survey of the ocean floor using sonar, said Melissa Ryan, a marine biologist and project manager of the non-profit Ocean Technology Foundation (OTF) in Groton, Conn.

But a key to the mission is ASA's modeling software, which takes a myriad of historical data and uses it to determine the best underwater locations to look for the ship's remains, Ryan said. ASA is a Narragansett, R.I.-based marine and freshwater environmental modeling software vendor that built a custom hybrid for the expedition out of two of its key products. Search and Rescue MAP (SARMAP), predicts the movement of drifting objects at sea for search and rescue planning, while OILMAP predicts the movement of oil spills on water.

The software is loaded on Windows-based laptops that continue to crunch the data in the hopes of pinning down more possible locations for the ship. The OTF, an undersea research and education service organization, next summer plans to use that data when it sends out an unmanned underwater camera to determine whether any of the targets are actual wreckage.

Researchers took information from old tidal schedules, eyewitness accounts of the ship's final battle from newspapers and archives -- along with old ship's logs -- and plugged it into the modeling software. It developed a carefully crafted list of at least five underwater targets that could be the ship, she said.

"It would have been pretty difficult, if not impossible, to try to incorporate all of the information that we had" without the modeling software, Ryan said. "If you can narrow the haystack down through simulations, then your search becomes that much narrower."

The challenge with finding the Bonhomme Richard is that contrary to popular belief, the ship didn't go under immediately but burned and continued to sluggishly sail in the North Sea for more than a day after it defeated the British ship Serapis. No one knows exactly where Jones' ship finally came to rest because the tides, winds, partial sails and ocean currents continued to push it atop the ocean.

Lee Dooley, a spokesman for ASA, said the company had to create a custom application from two off-the-shelf products because the expedition's needs were very complex. "[The ship] was impacted by more than just currents and winds," Dooley said.

Using its own algorithms, the ASA software aggregated the data to devise lists of possible targets. "It's a big probability matrix," Dooley said.

The expedition's mapping of target areas helped narrow down likely locations -- a crucial step before sending a remote camera to look for wreckage. Such cameras are good for identifying objects but not for finding something underwater unless the location is exact, Dooley said.

If the wreckage is found next summer, the expedition will gather underwater photos of the site, but no recovery operations will be done, Ryan said. An archeological mission to recover objects could take place in 2008 , but funding still has to be found for that work.