Shipwrecks:  Drift Model Lab.

The Battle of Flamborough Head between Bonhomme Richard and Serapis took place on Thursday, 22 September 1779, with the fighting between about 1830 and 2200 within view of the English coast.

From the end of the battle until about 1500 of Friday 23 September, the ships drifted with tide as the crew attempted damage control.  At around 1500 on Friday, the ships attempted to get underway, with the reports from land suggesting they were heading northeast toward Norway.  Bonhomme Richard sank around 1100 on Saturday 24 September 1779.  The log of  Serapis resumes at noon on Saturday, reporting a heading eastward.

We will investigate the motions of the ships during the 20 hours leading up the sinking, using the tidal current, a wind generated current, and a sailing motion. has a drift model for plastic trash, with option to download a CSV file 

Data files.  These data sets are not available outside USNA, and should not be disseminated outside USNA.

  • Automatic download inside MICRODEM by selecting the lab.
Map of the battle area.  This is a merge from the Shuttle Radar Topography Mission and EMODnet bathymetry, and shows the cliffs at Flamborough Head and the sand waves in the North Sea.
Tides model, from Proudman Oceanographic Laboratory

Ship motion models, from the BHR search team and presented at the 2009 USNA Naval History symposium

  • Sym_1: BHR sails due east (90˚ true) with a speed of 2 knots. Probably the extreme heading and the fastest possible speed, and the direction they did actually go after the sinking.
  • Sym_2, BHR sails due northeasterly with a heading of 30˚ true with a speed of 2 knots, the direction assumed by  British observers on land.
  • Sym_3, the ship had no headway and drifted with the tides. The marks the closest the ship could be to land.
  • Sym_4: the ship's heading is 50˚ true, intermediate between Sym_1 and Sym_2. It sails at 1 knot on Friday, and 2 knots Saturday. Damage control Friday allows increase in speed on Saturday.
  • Sym_5: the ship's heading is 50˚ true. It sails at 2 knots on Friday, and 1 knot Saturday. Slows down to transfer as many men and supplies from BHR as possible before sinking, after JPJ acknowledges the inevitable.


Discuss how you think oceanographic models can help select a search area for the Bonhomme Richard.  Insure that you discuss the following, and include appropriate graphics:


Last revision 1/30/2017