MSC’s project to ‘stretch’ all four the smaller cruise ships in their fleet is the most recent refit of its kind, but this practise has been around far longer than you might think!

MSC Cruises this year became the first cruise line in several years to undertake a major ‘lengthening’ project on not just one, but four of the cruise ships in its fleet.

All four of their Lirica-Class vessels (MSC Lirica, Opera, Sinfonia and Armonia) will be stretched by 24m in 2014 and 2015, adding passenger capacity and more public spaces. Work on Armonia has already begun.

Fred Olsen Cruise Line’s Balmoral is ‘stretched’ by 99-feet in the video above.

The last time a mainstream cruise line cut a ship in half to add extra length for cabins and public spaces was in May 2008 when Braemar was sent to Blohm & Voss by Fred Olsen Cruises to have a pre-built 102-foot mid-section inserted.

This came just five months after Balmoral’s length was increased by 98-feet at the same shipyard. But when did this trend begin, and why is it a popular refit undertaking by cruise lines for their smaller ships?

To cut a modern cruise liner in half, insert a pre-built mid-section and then weld her together again may seem technologically demanding to many, but in fact this ‘stretching’ or ‘lengthening’ practice for ships has been around since the late 19th century when the steam engine was beginning to replace sails as the primary means of propulsion at sea.

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In 1865, with the introduction of the compound steam engine at sea, shipping lines faced a major dilemma. SS Agamemnon was launched this year, featuring a large compound steam engine capable of producing 300hp – the greater power and efficiency gave her a range of 8,500 nautical miles between coaling, allowing her to operate a liner route between the United Kingdom and China.

The advantages of a compound or expansion steam engine over a simple steam engine were clear – because the steam was exhausted into successively larger cylinders to accommodate the higher volumes at reduced pressures, they provided more power and were more efficient, requiring less coal to be carried, which itself also made the operation of the ship more profitable as it was lighter. The one major drawback, however, was that these engines were much larger and would require shipping companies to sacrifice accommodation and storage space aboard existing ships if they were to be fitted.

The answer was to cut the ships in half and lengthen them to accommodate the new engines. This was first done in 1871 by Allan Line – at that time a leading cargo and passenger shipping service between Britain and the United States. Their head offices were in Glasgow, the global hub of engineering and industrial progress at the time, which perhaps influenced the line’s staunch belief in the feasibility of the new steam engine design.

Allan Line was so eager to have the new engines installed across their fleet, that between 1871 and 1874 they had six of their trans-Atlantic ocean liners cut in half and stretched by around 40-feet. Allan Line’s competitors soon followed, but advances in engineering and ship design were gathering pace at such a rate that ocean liners were becoming out of date within years of their launch.

City of Glasgow, launched in 1850, led the way in building iron ships with screw propellers rather than wooden paddle steamers for trans-Atlantic service

Inman Line, one of the big three trans-Atlantic passenger lines (alongside White Star and Cunard Line) led the charge in 1850 with the launch of City of Glasgow, which generated interest in replacing wood-hulled paddle steamers with iron-hulled screw-propelled ships.

This came five years after the launch of SS Great Britain, the world’s first iron-hulled screw-driven ocean liner, but crucially, Inman proved that this configuration was far more profitable and reliable than paddle steamers – a design that Cunard Line clung to well into the 1860s.

It was White Star Line, however, that put an end to the lengthening of existing ships with the launch of SS Oceanic, a revolutionary ship for her time, which introduced a number of new considerations in terms of passenger ship design that continue, by and large, to this day.

SS Oceanic (pictured here as a model) was the most advanced ocean liner of her time when she was launched in 1870 and brought an end to the stretching of existing ocean liners

For instance, it was the first passenger liner to place the dining room amidships and low in the hull where there was least movement at sea, the first liner to locate first class accommodations amidships for passengers’ comfort, and the first passenger ship to feature electric bells to summon a steward – an early form of the telephone found next to the bed aboard every modern cruise ship.

This 128m ocean liner set a new benchmark that required new builds to match the standard, and likely would have provoked a tonnage war among the big three shipping companies if it hadn’t been for the Panic of 1873, a major financial crisis that was known as the Great Depression (until the financial crisis of the 1930s eclipsed it).

In the modern cruise industry, we can trace the practise of cutting ships in half and stretching them back to 1978 when Royal Caribbean lengthened Song of Norway by 85-feet. In a sense then, just like the trans-Atlantic passenger service in 1871, the practise of lengthening cruise ships has been around since the very beginning of the modern cruise industry after it had found its feet transitioning from ocean liners to cruise ships.

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Unlike their early predecessors, today’s cruise ships are lengthened for reasons of accommodation and capacity, rather than engineering, but the result is the same – greater efficiency and therefore more profit. In the case of the modern cruise ship, greater then provides additional passenger cabins, which means more revenue for the cruise line, but with only a small increase to the cost of operating the vessel.

MSC Cruises ‘Renaissance’ program will cost the cruise line US $250-million in total, but will provide each of the four Lirica-class ships with more than 400 passengers in 193 cabins, as well as space for a water park, a crèche, teenager clubs and a new library. In essence, the ‘Renaissance’ program will provide MSC Cruises with four new cruise ships for the cost of one (each of the MSC ships being lengthened cost around US $250-million to build between 2003 and 2005).

According to 20th Century Liners.com, the following is a list of all the cruise ships that have been stretched to date (not including the four Lirica-Class MSC cruise ships).