During World War Two, the one campaign that most concerned Winston Churchill was the Battle of the Atlantic. As an island nation, Great Britain was totally dependent on sea commerce for providing oil, a large portion of required food supplies and almost any other type of resource necessary to fight modern war. As they did in World War One, the German submarine force of World War Two came close to winning the campaign and shutting down the supply pipeline to Britain.
In the Pacific Japan was in the identical position. However, the submarines of the USN were successful in their goal and Japanese shipping was eradicated. As the war progressed, the operational tempo of the Imperial Japanese Navy slowed and slowed because of the increasing lack of fuel. Fuel that was not forthcoming because of the catastrophic Japanese tanker losses to US submarines. By 1945 Yamato, the largest battleship ever built, had only sufficient fuel for a one way ticket to Okinawa.
Merchant seamen and the ships on which they served are the unsung heroes of naval campaigns. The two longest campaigns of World War Two, were the submarine against merchant shipping and escorts in the Atlantic and the Pacific. The ultimate victory for the glamorous warships depended upon the safe delivery of the products in the holds of the slow dowdy merchantmen. Very few kits have been forthcoming, that have modeled these merchantmen. That is starting to change.
WSW has just produced a kit that includes four models. Included in the set are a tanker, freighter, and two tugs. The kit, listed as accessory #A 001, provides much more than accessories, the models are complete in themselves.
I have a couple of minor concerns. There could have been a little bit more detail on the deck stations of the reservoir tanks. With wire or plastic rod you can add extra pipes and fittings for the cluttered deck of a tanker. WSW used "Aztec" steps to provide the numerous inclined ladders on the ship. If you wish, this is easily corrected by removing the Aztec steps with a hobby knife and adding your favorite photo-etched inclined ladders. My most significant concern is the casting of the catwalks. There are two catwalks, one running from the forecastle to the amidships superstructure and the second from the amidships superstructure to the aft superstructure. They are cast integral to the hull. As a consequence they have solid supports and a thin sheet of resin from the underside of the catwalk to the deck below. Using a hobby knife, you can remove the resin between the catwalk and the deck. It appears that it would take much more work to replace the solid catwalk supports with support posts, probably involving removing the entire catwalk and substituting the support structure. However, remember that WSW produced this set as an accessory kit. It may be a small notch less in traditional WSW detail but in return gives you a lot for your money.