Manannan | Isle Of Man Steam Packet

By: Steven Tarbox
Last updated:
Manannan departing Belfast. Copyright © Scott Mackey.
Manannan departing Belfast. Copyright © Scott Mackey.

Overview of Manannan

MANANNAN is the Isle of Man Steam Packet’s fast craft and operates a summer only service from the Isle of Man to Belfast and Dublin, as well as a more frequent service to Liverpool.  She is a 96m wave piercing catamaran built in 1998 by InCat at Hobart in Tasmania.

Early Years

MANNANAN was launched in 1998 named INCAT 050 (her hull number) for Incat Chartering Pty., a company related to the yard which built her.  At the time she was the largest fast ferry built In Australia.  She was quickly chartered out to TT-Line (Tasmania) who marketed her as DEVIL CAT on the Port Melbourne – Georgetown route in Australia from December 1998 to April 1999.  

From May 1999 she was chartered to Fast Cat Ferries for service in New Zealand across the Cook Strait between Wellington and Picton, marketed as TOP CAT, but this only lasted until the end of October the following year.  She was then laid up in Hobart, were she was constructed, awaiting a new operator.

Military Service

In July 2001 the US Military agreed to the charter of INCAT 50, a charter which would require some conversion to be undertaken to make the vessel more suitable for military use.  The initial charter was for a 1-year experimental period, where the feasibility of using the vessel for the transport of military vehicles, equipment and personnel would be assessed in both military and coastguard applications.  As a result the charter was funded by the US Army, Navy, Marines and Coast Guard.  Renamed USS JOINT VENTURE (HSV-X1), she was converted in-house by InCat to be capable of rapidly transporting 800 tons of military vehicles and equipment as well as 360 military personnel.

As part of the conversion a new 472 square metre helicopter deck (the first such landing deck fitted to a high speed craft) was installed aft to allow large military helicopters such as the SH-60 Seahawk to take-off and land from the vessel.  A new stern quarter-ramp, gantry crane for the deployment of a Rigid Inflatable Boat (RIB), and long-range fuel tanks were also fitted.

HSV-X1 Joint Venture.jpg
“HSV-X1 Joint Venture” by United States Navy photo by Photographer’s Mate 2nd Class Frederick McCahan – [1]. Licensed under Public Domain via Commons.

In addition to providing a rapid deployment solution for military equipment and personnel, USS JOINT VENTURE also proved herself as a command and control centre in combat operations.  Notably she deployed Navy SEALs and US Marine Corps Fleet Anti-terrorism Security Teams (FAST) in Mark V craft and Rigid Inflatable Boats in Iraq.  

Her successful deployment led to the US Military acquiring several further vehicle carrying catamaran vessels from both InCat and competitor Austal Ships, including fellow Irish Sea vessel DUBLIN EXPRESS (the former WESTPAC EXPRESS) which made her debut as a commercial vessel when introduced by Irish Ferries between Dublin and Holyhead in Spring 2018.

Return to civilian use

During 2008 the US Military charter of USS JOINT VENTURE ended and she returned to InCat at Hobart, reverting to the name INCAT 050.  On the 19th of May 2008 the Isle of Man Steam Packet Company announced that they had purchased the vessel for conversion back to civilian use as a replacement for their Fincantieri mono-hull fast craft VIKING.  At the time the Steam Packet stated that due to her previous use she had been used much less intensively than similar craft and so had less wear than craft of comparable age.

VIKING seen in Liverpool 26/07/08. Copyright © Michael Livie.
VIKING seen in Liverpool 26/07/08. Copyright © Michael Livie.

Journey to the UK

The contract for the conversion was awarded to marine design and engineering company Houlder, with Burgess Marine carrying out the conversion work.  INCAT 050 left Hobart on the 24th of June with around 90% of the materials required for her conversion onboard, arriving at the BVT Marine (now BAE Systems) dockyard in Portsmouth on the 16th of July for the work to be carried out.  She had travelled to Portsmouth via Fremantle, Colombo, Jeddah, the Suez Canal, Valletta, and Gibraltar.

Following a public naming competition with a prize of £1000, it was announced that the new vessel would be named MANANNAN (in manx mythology Manannan Mac Lir is god of the sea and protector of the Isle of Man) with the vessel christened with the new name in November.

Manannan publicity image. Copyright © Isle of Man Steam Packet company
Manannan publicity image. Copyright © Isle of Man Steam Packet company


The £3m conversion increased the passenger capacity of the vessel to 820 people, and was the largest conversion of a high-speed vessel ever undertaken at that time.  The helicopter deck and stern quarter-ramp added for military service were removed with a more suitable stern vehicle ramp fitted, reducing the weight of the vessel by around 45 tonnes.  The existing interior was completely stripped out to allow reconfiguration of the passenger spaces and a new air conditioning system installed throughout.  

In addition to the reconfiguration and refurbishment of the existing passenger spaces, the existing lower passenger deck was extended aft over the vehicle deck by 20.4m in the area previously occupied by the helicopter landing deck.  This allowed the construction of a new bar area and basic galley, as well as increasing the passenger capacity of the vessel with 229 new seats housed in this area.

The existing 32 passenger capacity sky lounge on the upper passenger deck was completely replaced, with the new larger facility holding around 160 passengers.  New lifts were fitted linking the vehicle deck to the main passenger deck, and the main passenger deck to the upper passenger deck (sky lounge).  In total around 760 square metres of passenger space was added, with Southampton based Trimline completing the fit-out of the passenger spaces to Steam Packet specifications.  The cost of acquiring and converting MANANNAN was in excess of £20m, more than the £18 construction cost of the vessel she replaced, VIKING, when new.

Manannan arriving in Belfast. Copyright © Alan Geddes.
Manannan arriving in Belfast. Copyright © Alan Geddes.

Isle of Man service

Following sea-trials off the Isle of White on the 1st of May 2009 and completion of all works, MANANNAN arrived in Douglas on the Isle of Man for the first time on the 11th of May.  Following open days at the Isle of Man Steam Packet’s ports and all necessary trials and crew training, MANANNAN made her first commercial crossing between Douglas and Liverpool with the 07:30 departure from Douglas on 22nd of May 2009.

In February 2013 the Shop, Forward lounge, Main Lounge, Bridge and Crew Mess were refurbished by Trimline.  The following year Trimline refurbished the remaining passenger spaces in that years refit.  During her winter 2014/2015 layover, MANANNAN was fitted with a removable mezzanine deck designed by Houlder which allows her to carry up to 100 additional motorcycles during peak periods such as the Isle of Man TT races.

Technical data

Side profile drawing of MANANNAN. © InCat
Side profile drawing of MANANNAN. © InCat

A full technical specification document in pdf format can be downloaded from the InCat website here (external link)


Further reading

Original Article Published: 30/04/14
Rewritten: 28/03/18
Last updated: 02.07.20 (rebuilt

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