A.R.A. "Almirante Irízar"
The research/supply icebreaker
A.R.A. "Almirante Irizar", ordered in 1975 by
the Argentine Government, was delivered on December
15, 1978 by Wärtsilä´s Helnki Shipyard,
Finland. The A.R.A. "Almirante Irizar" is of a
completely new type, dsigned for supplying the
Argentinean research stations on the antarctic
continent.A special requirement made of the icebreaker
was that it should be capable of overwintering in the
Antarctica with some 200 persons on board.
The vessel is designed and built to
the highest class of Det norske Veritas +1A1 and
included in the design is the Wärtsilä air-bubbling
system and also fin stabilisers are provided to decrease
the rolling of the vessel during the long voyager in
open sea to the antarctic continent. The stabilisers
were supplied by AEG Schiffbau and are of type AEG/Denny
Brown. The compressors for the air bubbling system were
supplied by Helsingor Skibsverft.
The hull design is
typical of icebreakers built at this yard with closely
spaced frames located in the conventional way amidships,
but perpendicular to the hull plating fore and aft. The
frames are supported by a network of heavy web famed
longitudinal girders. The maximun plate thickness in the
ice strake forward is 40 mm, the plating being
constructed of special quality steel of high impact
strength even at the low temperatures that the vessel
will encounter during her service life. All the steel
plates were supplied by Rautaruukki Oy.
Although the accommodation looks
somewhat square shaped in design, the standard of the
various cabins, messrooms and saloons is very impressive.
There is a high level of decor and width for the 100
passengers sailing with the vessel, in addition to the
crew, making a total of 233 persons onboard during the
operational time the vessel spends in Antarctica.
The accommodations is fitted with a
complete air-conditioning system is capable of
maintaining an inner temperature of 20ºC at an
ambient temperature of –27 ºC. During summer weather,
an inner temperature of 24ºc and a relative humidity of
60% can be achieved at an ambient temperature of
30 ºC and 80% relative humidity.
The air-conditioning system was
supplied by SvenskaFlaktfabriken. The galley equipment,
electric range and all the other galley equipment ( all
supplied in stainless steel ) the majority being
delivered by Instrumentarium Oy/Metos.
The refrigerated stores with
stainless steel panelling of a prefabricated modular
type were supplied by Huurre Oy. The vessel fulfils the
regulations of the IMCO (International Conference in
Marine Polution, 1973), and is equipped by the Wärtsilä
Ekenas Pottery factory. The sewage treatment plant has
being supplied by Chemie & Aparate GmbH. There is also
an incinerator for oil sludge and combustible waste, the
unit being supplied by Fredriksstad Mekaniske Verksted.
The primary power is supplied by
four Wärtsilä-SEMT Pielstick eigth cylinder PC 2.5 L /
400 medium speed, non reversible, four stroke diesels
engines built at Wärtsilä´s factory at Vasa. The units
are directly connected to AEG generators wich in turn
feed the vessel´s propeller motors. There are two d.c.
propellers motors of double armature type each with an
output of 2975 kW. These units are also of AEG
manufacture and operate between 100 and 200 r.p.m.
The propeller motors drive two cast
stainless steel propellers designed with bolted blades.
The propellers are of the Helsinki Shipyard´s special
design and manufactured by Wärtsilä´s Dalsbruck
steelworks. The auxiliary power is supplied by four
Wärtsilä diesel engines type 624 TS, each with an output
of 660 kW and each coupled to an AEG synchronised
The steering gear comprises an
electrohydraulic steering gear supplied by the yard and
this operates a rudder of welded construction. The stern
frame is , however, fitted with an ice knife to protect
the rudder during reverse manoeuvering.
A special feature of the A.R.A.
"Almirante Irizar" is the Canadian manufactured RAS
system, i.e. a special helicopter take-down winch, wich
makes the helicopter ladings possible also during bad
weather conditions. The 16 t hydraulic cranes for
handling snow cats and cargo were supplied by the yard.
The vessel is also fitted with a
Rauma Repola electric towning winch, fitted with
automatic wire length and tow type force control. The
unit has a maximun pull of 60 t.