The class was introduced in 2002 to serve the tidal reach of the River Thames, which had not previously been covered by an RNLI rescue service, as a result of a much delayed enquiry into the Marchioness disaster in 1989, in which 51 people died.

[2] An E-class boat also originally operated from Gravesend Lifeboat Station to the east of London, but it proved less suitable for the more estuarine conditions found there and was replaced in 2008 with an Atlantic 85, B-827 Olive Laura Deane II.

It is made of an aluminium alloy with a closed cell polythene foam collar, and is powered by two Steyr marine diesel engines delivering 240 horsepower (180 kW) each at 4,100rpm and driving Hamilton waterjets.

This combination gives the boats a maximum speed of 33 knots (38 mph; 61 km/h) and the extreme maneuverability which is essential to enable crews to reach casualties in the fast flowing river.

It has a glass epoxy-resin composite hull with a detachable polyurethane covered solid closed-cell foam collar, and is powered by two Volvo marine diesel engines delivering 435 horsepower (324 kW) each at 3,300rpm and driving Hamilton waterjets.