How Well Do You Know Your Lifeboats? Part III – The ‘D’ Class Inshore Lifeboat (ILB)

The third blog in our series ‘How well do you know your lifeboats’  focuses on Margate’s ‘D’ class Inshore Lifeboat (ILB).  The ‘D’ class lifeboat has been a workhorse of the RNLI for over 50 years, which was first introduced in 1963 and has saved thousands of lives ever since. The design of the inflatable ‘D’ class lifeboat continues to evolve to meet the changes in operational demand and technology.

The ‘D’ class is a highly manoeuvrable craft and can operate closer to the shoreline than it’s all-weather lifeboat counter parts. The ‘D’ class definitely comes into her own for searches and rescues in surf, shallow water and confined area’s such as up close to cliffs, amongst rocks and even inside caves.

There are 110 lifeboat stations that currently have the very latest IB1 type ‘D’ class lifeboat. With a top speed of 25 knots, ‘D’ class lifeboats can endure up to 3 hours at sea at this speed on search and rescue taskings which is a critical factor when lives are at risk.  Margate’s first ‘D’ class inshore boat came on service in 1966, with the latest D-841 Alfred Alexander Staden going on operational service on 5th October 2019.


Most ‘D’ class lifeboats are launched from a trolley with the assistance of a launch and recovery vehicle such as a tractor or landrover (Margate’s ILB is launched using a tractor).  Some stations launch their ‘D’ class by lowering it into the sea using a davit system which is a shore-mounted crane.


Safety Kit Carried

The ‘D’ class lifeboat carries night vision equipment, a searchlight and parachute illuminating flares to light up a search area, helping to maintain crew safety as well as help locate those in need of help.

Medical equipment is stowed in a pod on the bow which includes oxygen, resuscitation kit, responder bag and ambulance pouch.

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Margate’s Inshore Lifeboat taking part in a mock rescue drill at the Margate Blue Light Community Event 2019

Technical Stuff

2–3 (must include a Helmsmen)

Survivor capacity:

Maximum speed:
25 knots

Range / endurance:
3 hours at maximum speed


Beam / width:

Draught / depth:

Displacement / weight:

Fuel capacity:
68 litres

1 x Mariner engine at 50hp

Hypalon-coated polyester

All lifeboats have a unique identification number.
The first part indicates the class so ‘D’ class lifeboats start with D.
The numbers after the dash refer to the build number. So the first ‘D’ class built in the current IB1 design was given the number D-600.

Why not find out more about the RNLI’s inshore lifeboats by watching this video


While lifeboat stations remain operational and are continuing to launch to those at peril at sea, they are not currently open to visitors. 


Useful links

Margate Lifeboat Facebook page

Margate Lifeboat web page

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As the clocks go back this weekend, are you Winter Water Aware’?



Royal National Lifeboat Institution