D-class lifeboat (IB1)

The D-class lifeboats are inflatable boats serving in the RNLI inshore lifeboat fleet as well as a number of Independent Lifeboats around the UK and Ireland. Although they are known as the "IB1" at times, they are the latest development of the D-class lifeboat and as such are mainly referred to as a "D-class".
This class of lifeboat is one of the smallest operated by the RNLI, and they are a common sight at lifeboat stations round the coast. Unlike other members of the ILB fleet, the D-class does not have a rigid hull. All others with the exception of the Arancia, hovercraft and all-weather lifeboat tenders are rigid inflatable boats.
The IB1 normally has a crew of three or four and is primarily used for surfer/swimmer incidents as well as assisting in cliff incidents where the casualty is near the water. The very nature of its work requires a swift response, and the IB1 can normally be afloat very quickly.
As of February 2020 the minimum crew for an RNLI IB1 was raised from 2 to 3. Some Independent Lifeboats have different crewing levels to the RNLI.
All of the following fleet details are referenced to the 2026 Lifeboat Enthusiast Society Handbook, with information retrieved directly from RNLI records.