MT Indiga

MT ''Indiga'' ( rus, Индига) was an ice-strengthened product tanker that sailed under the Finnish flag in 1976–2003 and under the Russian flag in 2003–2021. After her modernization in 1994 she became the second merchant ship, after her sister ship ''Varzuga'', to be equipped with an electric azimuth thruster called Azipod.Juurmaa, K et al.: The development of the double acting tanker for ice operation, Aker Arctic Technology Inc.
2001
an
2002
.

History

''Lunni'', built in 1976 by Werft Nobiskrug GmbH in Rendsburg, Germany, was the first ship of a series of four arctic product tankers ordered by a Finnish oil and petroleum products company Neste Oyj in the 1970s. The ships were given names after Finnish seabirds and the silhouettes of their namesake birds were painted on the side of the ships' superstructure. ''Lunni'' (Atlantic puffin) and ''Sotka'' (Aythya) were delivered in 1976 and ''Tiira'' (tern) and ''Uikku'' (grebe) in the following year. Until the 1990s the ships were used mainly to transport oil products in the Baltic Sea.

In 1993 ''Lunni'' made three consecutive voyages from Arkhangelsk to the Yana River in Siberia along the Northern Sea Route. The tanker was assisted by nuclear-powered icebreakers in the Vilkitsky Strait, but was under constant escort by Russian icebreakers only from Dikson Island to the Khatanga River.Muhlerin, N et al.
Northern Sea Route and Icebreaking Technology
, pages 13-14. Cold Regions Research and Engineering Laboratory (CRREL), 1994. Retrieved on 2010-02-05.

In 1994, a year after her sister ''Uikku'', ''Lunni'' was also chartered to Arctic Shipping Services to ship petroleum products in the Arctic Ocean. After ''Uikku'' 's successful refit her propulsion machinery was also modernized for navigation in the harsh ice conditions of the Arctic Ocean in 1994. Her ice-strengthening was later increased as well. In the following years ''Lunni'' operated in the Baltic Sea in winter and in the Northern Sea Route during summer months.Juurmaa, K et al.
New ice breaking tanker concept for the arctic (DAT)
. Kvaerner Masa-Yards, 1995.

Fortum sold ''Lunni'', mainly due to her age exceeding 25 years, to Murmansk Shipping Company in 2003. She was renamed ''Indiga'' (''Индига'') after the Indiga River. As Fortum is a state-owned company, the selling of two oil tankers capable of navigating in severe ice conditions resulted in a written question to the Parliament of Finland by Representative Pentti Tiusanen about whether the ships should be retained in Finnish control as they could be used to lighten a grounded oil tanker in harsh winter conditions.KK 137/2003 vp
Pentti Tiusanen /vas

The ship has since been used for oil transportation in the Arctic Ocean. Along with her sister ship ''Varzuga'' (ex-''Uikku''), sold to Russians at the same time, she has been involved in transporting oil from an oil terminal in the Ob Bay of the Kara Sea through the Kara Gates, the strait between Vaygach and Novaya Zemlya, to FSO ''Belokamenka'' in the Kola Bay of the Barents Sea.Bambulyak, A and Frantzen, B
Oil transport from the Russian part of the Barents Region, Status per January 2009
page 41. Retrieved on 2010-02-05.

''Indiga'' was sold for scrap in 2021.

Incidents

On March 16, 2009, ''Indiga'' collided with the Russian nuclear-powered icebreaker ''Yamal'' in Yenisei Gulf in the Kara Sea. The tanker, carrying only ballast at the time, sustained a 9.5-meter crack on the main deck. No damage was reported to the ''Yamal''.Ice-breaker collides with tanker in Arctic Ocean
PortWorld News, 2009-03-30.Nuclear powered icebreaker collided with oil tanker
BarentsObserver, 2009-03-24.

On 19 July 2010 ''Indiga'' collided again, this time with her sister ship ''Varzuga'', while being assisted by two nuclear icebreakers in difficult ice conditions. The bow of ''Varzuga'' and the stern of ''Indiga'' were damaged, but neither vessel lost seaworthiness and there were no spills.
. BarentsObserver, 2010-07-19.

Design

''Lunni'' and her sister ships were designed to be able to navigate in the ice conditions of the Baltic Sea independently without icebreaker assistance and maintain a moderately high speed in ice. For this purpose they had more power than an average Baltic tanker and were normally required to use only 50-75% of the full engine power in iceHänninen, S
Ship based observations onboard MT Uikku during the winter 2003
, 11/2003. — in normal operation only one of the two main engines was coupled to shaft, with the other remaining in reserve for difficult ice conditions.Gallin, I. et al. Ships and Their Propulsion Systems - Developmentsr in Power Transmission. Lohmann & Stolterfoht GmbH, Witten, West Germany. . The highly raked stem, similar to those in traditional icebreakers, was designed to break the ice by bending it downwards under the ship's weight. The ships were also equipped with an air bubbling system to reduce friction between the hull and ice.Mulherin, N et al.
Development and Results of a Northern Sea Route Transit Model
pp. 15-17. Cold Regions Research and Engineering Laboratory (CRREL), 1996. Retrieved on 2010-02-05. To prevent pollution in case of grounding the ships were also built with double hulls and conformed to the IMCO regulations in respect of segregated ballast tanks even though they were regarded only recommendations back then.

Modernization

A year after ''Uikku'' 's successful refit ''Lunni'' was also extensively modernized by Kværner Masa-Yards' Helsinki New Shipyard in 1994 and became the second merchant ship to receive a newly developed electronic azimuth thruster, Azipod. Her original MaK 12M551AK main engines (2 × 5737 kW), reduction gearbox, shaft generators, controllable-pitch propeller and rudder were removed and replaced with Wärtsilä Vasa marine generating sets and an 11.4 MW electric propulsion unit. Being one of the early designs the Azipod unit in ''Lunni'' was of the so-called "pushing" type with an aft-facing propeller instead of the more efficient "pulling" set-up usually used in modern Azipod-equipped ships.Photograph of ''Lunni'' 's Azipod unit
, Aker Arctic Technology Inc.

As with ''Uikku'', upgrading the propulsion machinery dramatically improved ''Lunni'' 's manoeuvering and icebreaking capabilities, especially when running astern. Even though the ship's stern wasn't originally designed or shaped for icebreaking, ice resistance astern in level ice was only 40% of that of when running ahead despite the icebreaking bow. The modernization of ''Lunni'' and ''Uikku'' also further proved the feasibility of Azipod in icebreaking ships and the double acting tanker (DAT) concept as navigation in the severe ice conditions in the Northern Sea Route sometimes required the ship to be turned around and run astern to break through ice. The refit also increased her speed from 14.5 to 17 knots despite the propulsion power remaining roughly the same.

References

External links

Murmansk Shipping Company

Indiga

{{DEFAULTSORT:Indiga
1976 ships
Oil tankers
Ships built in Rendsburg
Murmansk Shipping Company