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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 Atlantic 85 is one of the new generation of RNLI B-class Atlantic inshore lifeboats, first developed by the RNLI from a design originated at Atlantic College, South Wales.
With a crew of four, and two inversion-proof 115hp petrol engines, the lifeboat is capable of speeds in excess of 35 knots, and is fitted with a manually operated righting system which, combined with her inversion proofed engines, allows her to remain operational even after capsize.
At Sheringham the boat is launched from a DO-DO (drive on - drive off) trolley directly into the sea via the slipway.
Equipped with the latest in electronic equipment including radar, a chart plotter and VHF radio direction finding equipment, she has an endurance of 2.5 hours.
The Oddfellows has an overall length of 8.3m,
a beam of 2.8m and a draught with engines raised of just 50cm
Hull
The hull is made from a carbon fibre and foam core laminate that minimises the internal structure whilst maintaining overall stiffness. The foam is a very tough material that has the ability to absorb and recover from high impact loads such as pounding through waves at speed. 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.
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, radio operator behind him to the port side,
navigator to starboard and the fourth man's seat behind them. All crew positions
have foot straps fitted to the deck to allow the crew to 'ride the
bumps'. Although there are only four crew seats the boat
is capable of carrying over twenty 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 to seas, 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 high 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.)/Radar control & display screen which provides co-ordinates, estimated
speed, and guidance to programmable waypoints (although waterproof
charts of the local area are stored in
pockets in the console in case necessary). The 85 also has DF radio which will indicate the compass heading that a calling station is coming from - very useful when trying to find a vessel in radio contact but poor visibility.
The middle 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 - red for distress
and 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
to tow stricken vessels to safety.
 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 the compressed gas 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.
Engines
The twin 115hp Yamaha engines are capable of taking the boat to a speed
of 35 knots, both are petrol, 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.
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