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The current Sheringham
lifeboat is an Atlantic 85 rigid inflatable boat named 'The Oddfellows' after The  Manchester
Unity Independent Order of Oddfellows who donated the cost of
this boat.
The below information relates to the previous boat the Atlantic 75 and will be updated to the Atlantic 85 information shortly...
Atlantic 75 class lifeboats, developed at the RNLI's Inshore Lifeboat
Centre at Cowes, are the fastest marine boats in the fleet, with
a maximum speed of 34 knots provided by the twin 70hp outboard engines.
Manchester Unity of Oddfellows has an overall length of 24ft (7.3m),
width of 8ft 8in (2.64m) and a draught at rest of only 26in (0.66m).
She is self righting by means of a gas bouyancy bag on a framework
above the engines and has been fitted with a new type of water ballast
system which may be emptied and filled while at sea.
Hull
The rigid portion of the hull is made of GRP (Glass Reinforced Plastic),
a composite material consisting of plastic (polymer resin) with
glass fibre reinforcement. This material is stronger than wood,
non-corroding, invulnerable to attack by marine  organisms
and easily moulded into complex shapes. The hull is shaped with
a deep V forward to a flat run aft, the deep V bow gives the boat
excellent directional stability when underway and the flat run assists
in getting the boat up on the plane quickly and on the occassion
that the boat needs to be beached she will sit upright.
The bow contains ballast tanks which are filled with water to provide
the boat with more stability and may be filled and emptied while
at sea by the the use of a handle near the helmsman which lowers
a scoop to fill the tanks while the boat is underway.
Two stainless steel fuel tanks are installed in the hull, one to
port the other to starboard, both are embedded in polystyrene and
can be used to feed each engine independently or one tank to both
engines if needed. The tanks each hold 12 gallons of unleaded petrol/oil
mixture (50:1) and will allow the boat to travel at full speed for
about 3 hours, covering a distance of approximately 90 nautical
miles.
Sponson
The sponson is the inflatable tube (made of tough Nylon weave) which
runs around the outside of the boat allowing the boat to operate
in rough seas and provides fendering when going alongside other
vessels. The sponson is composed of a number of separate compartments,
if one is accidentally punctured then the others will remain inflated
although the boat is still capable of floating without the sponson.
 Console
The console is fitted in the centre of the boat and provides the
helsman's controls and seating for the crew, with the helmsman at
the front, and the radio operator behind him to the port side and
other crew man (navigator) to starboard. All crew positions
have foot straps fitted to the deck to allow the crew to 'ride the
bumps'. Although there are only three crew seats the boat
is capable of carrying twenty two people if necessary.
At the very front of the console is the anchor, warp and chain,
when deployed the anchor warp is passed through the fairlead at
the very front of the boat which will ensure that the boat is always
held head on, it also prevents wear on the sponson and will prevent
the possibility of capsize caused by an anchor rope going over the
side of a sponson.
The helmsman has control of the steering wheel and single hand operation
of the engine controls (throttles, gears and engine tilt/trim).
Also on the helmsmans console are the illuminated compass,
depth sounder, various switches for controlling navigation lights,
engine start/stop, individual tachometers and motor thigh temperature
warning lights.
Behind the helmsman on the port side is the water-tight VHF radio,
hand microphone and loud speaker, (the helmsman also has a radio
speaker and mike in his helmet which is controlled by a switch on
the throttle handle). Directly behind the helmsman is the Global
Positioning System (G.P.S.) which provides co-ordinates, estimated
speed, and guidance to programmable waypoints (although waterproof
charts of the local area are stored i n
pockets in the console in case necessary). The crew seat on
the console can be lifted to gain access to the petrol tank filler
caps and a locker for gear such as a foot pump for topping up the
sponson and an aerosol operated fog horn. In another locker
on the console a number of flares are stored, 2 x red for distress
and 6 x white parachute flares. The parachute flares are used
when trying to locate a casualty at night. The parachute flares
are fired into the air to produce a very bright light which slowly
descends on a parachute illuminating a large area.
To the rear of the console is the 35m towing rope on a reel which
is used in conjunction with the tow bar (stored along side the sponson)
to tow stricken vessels to safety. The tow bar can be fitted to
the a-frame at the stern of the boat and the tow rope then passed
over it to provide a safe method of towing vessels while keeping
the rope out of the lifeboat's propellors.
Roll-bar
The roll-bar, also known as the A-Frame or Gantry, is located at
the very stern of the boat and supports the self righting bag, navigation
lights and aerials. In the event of a capsize in very shallow
water the roll-bar will give some protection to the crew, motors
and console.
The self righting airbag is stored on top of the a-frame and may
be inflated using CO2 cylinders located at the base of the rollbar.
If the boat should capsize a handle at either side of the boat outside
of the stern (ie, accessible from the water when the lifeboat is
inverted) will empty the contents of one of the gas bottles into
the airbag which will then cause the boat to roll the right way
up.
Also mounted on the a-frame is the oxygen bottle and equipment for
administering oxygen to casualties.
Engines
The twin 70hp engines are capable of taking the boat to a speed
of 34 knots, both are petrol/oil mixture two stroke, water cooled
and each power a propellor by a vertical drive shaft through a remotely
controlled gearbox. Each gear box offers one forward, one reverse
gear and a neutral position. The engines may be operated completely
independently of each other if required. The RNLI has made
some specific modifications to the engines to allow them to be immersion
proof -
- a mercury switch operated solenoid valve will shut off the air
inlet and cut off ignition if the boat reaches an angle of heel
of 90 degrees
- the exhaust system has a u-tube assembly and one way exhaust valves
to prevent water entering when the engine is inverted,
 Other
equipment
First aid kit
Portable VHF radio
Nightscope
3 x Paddles (one separates for use in emergency steering)
4 x knives
Toolkit
2 x Spare propellors
Sea Anchor / Drogue (stored at bow of boat used for holding the
head of the boat into the sea in case of capsize or when normal
anchor would not be applicable)
Throwing lines fitted to quoits at either side of the sponson
2 x 20m mooring ropes
Small hand held torch
Halogen spotlight torch
Fire extinguisher
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