NAS member Karen Moule has been diving for over 30 years and has always had a love of diving on shipwrecks. Since attending NAS’s online course on Metal Shipwrecks, it has given her a whole new appreciation for them.

Understanding & Recording Metal Shipwrecks Online Course - 1st May 2021

Ever since I started diving on metal wrecks, I really enjoyed trying to understand how a twisted mass of metal had come to rest in this final position. Unfortunately, I didn’t have a great understanding of the structure of ships, the individual features, and even where those were supposed to be. Very slowly, over time I learnt. 

The NAS course ‘Understanding and Recording Metal Shipwrecks’ is a course I wish had been available in those early days! Jane Maddocks who hosted the course took us through a methodical and clear timeline of how metal ships even came to be - starting with the first paddle wheel steamers circa 1800, through the first iron ships, the invention of the screw propeller, to steel ships, the use of boilers and compound engines, through to the diesel fuelled ships of today.

The archaeology of ships delivers many insights, which in turn demonstrates how they have impacted our history, from a technological, societal, trade and environmental point of view. 

We looked at the different types of ships that have been in use since metal ships started to be built: Merchant ships, passenger vessels, warships, fishing vessels, as well as less generic categories like dredgers, barges, and even Mulberry Harbours.  


Having a clearer understanding of the function of a vessel helps to identify how the space on board is organised. For example, the bridge on a tanker will be at the stern, but on a battleship will be more in the middle, and on a smaller fishing boat, nearer the bow. 

Should you be diving on an unknown wreck, there are clues to what the function of that vessel may have been, which will help to confirm the type of ship it was. 

How it sank can make that identification harder depending on what actually happened, as Jane explained the different ways a ship could end up on the seabed – explosion, collision, hull breach, shifting cargo, ramp failure or scuttling. Each method of sinking will result in the final position of the wreck being very different. At this point we had an exercise to look at some photogrammetry recordings of two different wrecks, to put our learning into practice. It’s interesting how quickly you can make observations and identify clues to deduce facts about a wreck. 

So having found a wreck, considered its potential function, and how it sank, it needs to be recorded for a variety of reasons: to aid the identification of the ship, confirm the form and function of the vessel, record the ‘here and now’ in order to be able to monitor degradation over time, and allow for attention on specific details. This recording can be done using sketches – rough and measured, video footage, photographs and photogrammetry – and depending on what part of the wreck you’re recording will depend on the preferred method. 

All of this work then helps to make that all-important identification, which involves research. Jane listed the essential resources to find information about a shipwreck, including from Lloyds, Admiralty documents from the National Archives, Board of Trade, and local newspapers reporting on incidents at sea, to name but a few. 

As I say, I wish this course had been available when I started diving on wrecks. It would have made my dives even more enjoyable. Jane was able to highlight great examples throughout from her extensive experience, and others on the course also contributed useful information at key points. I would highly recommend this course to anyone interested in understanding more about metal shipwrecks and how to go about recording them.