SO482A.  Historic shipwrecks: Science, History, and Engineering

Last Day of the Bonhomme Richard


Lesson Objectives:

Read the following narratives of the battle:


Run a simulation of a frigate from the Age of Sail:

We will approximate the winds on Friday, Saturday, and Sunday September 24-26, 1779 as being southerly with a speed of 17 knots.

You will run the Surprise simulator to investigate the effects of the battle damage to the Serapis.  The simulator was not designed for this, and you will note that its depiction of the sail plan did not expect users to remove sails as we have done because the scaling does not look right.  Despite this limitation, the simulation gives us some idea of how the battle damage might have affected Serapis.

Download the simulator, with three models, and unzip it:

Directions with screen captures.

In all three models, the ship starts out sailing toward 45šT with all available sails set.  We are running with an automatic helmsman and yardsman, who will attempt to carry out your orders.  If you are adventurous, you can run multiple versions of the simulation at the same time.  You can also check the help file and look at other options, including changing the sizes of the sails which is how we are simulating damage.

Start the Surprise program, and pick "File, Open" and pick the model you want to run.  Run the simulation until the ship appears to be in a steady state (speed and heading not changing), and then fill in the table below (you will need this for the quiz).

  Heading Speed (knots) Leeway (degrees)
Winchelsea 45šT    
Serapis_1 45šT    
Serapis_2 45šT    

Adjust the ship's heading to 90šT, by clicking on the helmsman button so "await orders" appears, then click again, and set the heading to the desired course of 90šT.  Run the simulation until the ship appears to be in a steady state or the ship appears unable to respond to your request, and then fill in the table below (you will need this for the quiz).

  Heading Speed (knots) Leeway (degrees)
Winchelsea 90šT    
Serapis_1 90šT    
Serapis_2 90šT    

Adjust sail on the Serapis_2 model, using the "Decrease sail" button on the top of the screen, and see if can you get to a speed of 2 knots to the east?  This was what the log reported for Saturday afternoon, and if the model is accurate and the logbook speed is accurate, this might provide information on how much sail they had up, and if in fact they could have sailed to the east. 


 Return to course syllabus


References:


Last revision 4/13/2011