The high temperatures in the boiler room were problematical; this was to some extent alleviated by installing bigger fans. Steaming at speed tended to push the bow into the water, making the already poor sea-keeping worse. To fix this a bulbous "swan bow" was added, which also incorporated a 'quick blowing' ballast tank to improve handling. Nevertheless, there were still problems with seaworthiness, such as that in a heavy storm, sea water could enter the boat through the short twin funnels and put the boiler fires out. The boats suffered numerous accidents, largely caused by their poor manoeuvrability when operating with the surface fleet, including: