The first of AAL’s ‘super b-class’ premium heavy lift vessels passes key construction stage with flying colour

In late December, at the CSSC HuangPu WenChong Shipyard in China, the first of AAL Shipping’s next generation 32,000 deadweight (DWT) ‘Super B-Class’ fleet, the AAL LIMASSOL, was floated out into the water from dry dock and moved to pier. This milestone marks the third of four crucial stages in her construction prior to delivery and even the most important – the stages comprising steel cutting, keel laying, launching and finally sea trial.

Yahaya Sanusi, Deputy Head of AAL’s Transport Engineering Department explained, “With all major equipment installed on board, launching provides the perfect test of a newbuild’s water integrity and stability. Once successfully completed, engine shafting, hatch covers, pontoons and even cranes are finally adjusted. This is primarily because the hull structure of the vessel flexes into a shape which is closer to its normal operating mode and, with ‘digital manufacturing’, the results are extremely good and within the required engineering tolerance levels.

“By this stage, approximately three quarters of the work onboard has already been completed and many of the additional work packages can be built simultaneously and later assembled on board. The AAL LIMASSOL will go for sea trial in April 2024 before her delivery to AAL in May – so she will have been on the water for over five months.

Rangel Vassilev, Director of Newbuilding Projects at AAL’s sister company, Columbia Shipmanagement, added, “In general, any work that can be done before launching is a benefit, as after this stage access is obviously harder and jobs take longer. At the yard where the six Super B-Class vessels are being built, it typically takes about 60 days after launching to prepare a standard container vessel for sea-trial. However, the SUPER-B class is a much more complicated build. Its hatch covers, tween decks, three heavy lift cranes – featuring a 700-tonne maximum tandem lift capacity – and the all-new ‘AAL Extendable Eco-Deck System’ must all be in place and tested during this stage and honed prior to sea trial. The AAL LIMASSOL is also the first of her fleet, so we anticipate her equipment commissioning and mooring trials to take over 120 days.”

Sanusi concluded, “Our next step is to undertake mooring trials of the AAL LIMASSOL’s machinery and cargo handling equipment and prepare her for the final sea-trial stage. At that point, speed, fuel consumption and other manoeuvring characteristics will all be tested. For a naval architect this is critical as it will demonstrate how well the vessel performs and responds in water – especially as up to this point performance has been calculated in tank tests and using theoretical algorithms.

“We commissioned the Super B-Class with the aim of its six ships being the finest, premium multipurpose heavy lift vessels in the water and therefore they are unique in so many ways and harness state-of-the-art design and cargo handling technologies. For this reason, we planned a construction schedule that would allow all the time needed for every facet of the vessels to be fully tested and realised. We are delighted that everything is proceeding as planned and our customers can expect the first of the fleet to be operational by May ’24.”