July saw a technical triumvirate of Marlin divers heading to Portland on the south coast of England for a weekend of deeper diving. Driving down on Saturday morning, Martin, Rob, and Ian joined the Scimitar dive boat and skipper Nick for a ropes-off at 2 p.m. The target was the wreck of the Salsette, which lies in Lyme Bay.
The SS Salsette is a P&O ocean liner launched on 2nd April 1908 and torpedoed by the German submarine UB-40 on 20th July 1917. The ship sank quickly, and fifteen engine room crew were lost, although all the passengers escaped. She could carry 140 first and 121 second-class passengers and deliver mail and general stores from London to Bombay.
The ship is modest at 5,842 gross tonnes compared to P&O’s 10,000-tonne passenger ships, but at 20 knots, she was fast. The Salsette is 134.1 metres long and has a beam of 16.2 metres. She now lies on her port side in 46 metres of water.
The visibility on the wreck was variable, ranging from about 3–5 metres. The water temperature was 15ºC at depth. We descended the shot line close to the stern and began the dive by exploring the steering gear. She originally had two bronze propellors, and the starboard one has been removed, with the flange visible together with the rudder. The port propellor is alleged to lie just below the seabed level.
Progressing slowly towards the bow, the ship was collapsing. We looked into various openings in the deck that hinted at an engine room containing two 10,000-horsepower quadruple expansion steam engines. A mast remains, and we scootered along it and back.
Most of the decking had rotted away, and it was possible to swim under the rib-like deck supports that were now rotated nearly ninety degrees to frame our lefthand side. Towards the bow, the teak decking had avoided hungry shipworms and was amazingly still present. Here, bollards, capstans, and some railings could be identified.
After 40 minutes, it was time to leave. Ascending a delayed surface marker buoy, we were back on the boat after 86 minutes.
What is technical diving? Journalist Michael Menduno coined the term technical diving in the 1990s, but the definition has yet to be universally agreed. Some diver training agencies classify it as including mandatory decompression stops. However, BSAC teaches this at Sports Diver, a recreational course. It is better to consider it all recreational diving, but as we go deeper, we must take more equipment and have more complex procedures. We can call it ‘ technical ‘ at some point, perhaps below 40 metres or when accelerating decompression. For this trip, two of the cohort were diving closed circuit rebreathers, while the open circuit diver was accelerating decompression with a gas switch to 50% nitrox during the ascent. All three were breathing helium-containing gases. Two had diver propulsion vehicles (scooters).
Sunday was an earlier start, with ropes off at 8 am. Today’s target was the wreck of the SS Château Yquem, which lies in 47 metres of water, having been torpedoed by UB-40 on 30th June 1917 while carrying ballast from Dunkirk to Barry.
A string of lobster pots set across the wreck hampered the installation of the shot line. A second shot was installed at midships, and we carefully descended onto the wreck with better visibility than the previous day.
This time, we decided to scooter to the bow to get our bearings, and then we returned to the stern for a slower examination of the wreck. The steering quadrant, which lies upright on the seabed, is visible on the wreck. Some of the propellor shaft is visible at the stern, but the propellor has been salvaged.
Heading back towards the bow, the enormous triple expansion steam engine that powered the single steam screw stands proud. In front of the engine were the remains of the boiler. The forward double mast lies across the ship, with winch-gear at the base.
The bow is intact, and the railing remains can be seen above the slowed anchor and chain still going through the hawsepipe from a winch.
With the bottom time reaching 45 minutes, we scootered back to the stern before ascending on a DSMB again, returning to Scimitar for tea and medals a minute over our planned 90-minute run time.