The D class has been the workhorse of the service for 40 years. It is small and highly manoeuvrable, making it ideal for rescues close to shore in fair to moderate conditions. It has a single outboard engine and can be righted manually by the crew following a capsize. The design of the D class has continued to evolve since its introduction. The details given are for the latest version that was introduced in 2003

The Trent class lifeboat is designed to lie afloat, either at deep-water moorings or at a berth. Introduced in 1994, it shares the same hull shape as the Severn class but is a smaller version. The sheerline sweeps down for ease of survivor recovery. As with the Severn, its propellers are protected so it can take ground without damage.