Ferry Design: Monohull Versus Catamaran

An analysis in efficiency and operability in the medium-speed, medium-sized ferry sector.

This article was written based on the research conducted by Dr. Alf Baird, former Professor of Maritime Business at Edinburgh Napier University.
sea transport ferry operations

In the small to medium-size ferry industry, controversy continues about which hull type is greater in efficiency and operability: the monohull or the multi-hull. Much of the debate centres around the long-held belief that multi-hull ferries have an operational weakness in comparison to their single-hull competitor.

But today, this belief isn’t necessarily the case, considering the increasing number of medium-speed RO-PAX catamarans that have been built in the past few decades.

So which hull-type is best for ferry operations?

Let’s look at the one-on-one comparison study conducted by Dr. Alf Baird between a medium-speed monohull and a multi-hull catamaran RO-PAX ferry. Both ferries have similar vehicle deck space, speed and operate within fairly short island routes that occasionally experience severe weather and rough seas.

The considerations in the comparison study were:

  1. Efficiency:
    Each ferry’s design aims to minimise a vessel’s block coefficient, its resist­ance, and its displacement, while striving to increase the revenue earning deadweight.
  2. Motion Sickness Incidence:
    ‘MSI’ or Motion Sickness Incidence is a function of motion and extent of time. Catamarans have a different motion to monohulls; however, this doesn’t necessarily mean the MSI is greater for a catamaran than a monohull.
  3. Manoeuvrability
    Catamarans are known for having the ability to manoeuvre in confined port areas even during strong winds due to their widely spaced hulls. Monohulls tend to experience more cancellations due to unfavourable weather and are much more difficult to handle in confined port spaces.
  4. Sea Keeping
    ‘Seakeeping’ refers to a vessel’s ability to withstand and maintain speed during poor weather conditions and high waves.
  5. Other Factors:
    Each ferry’s overall level of safety, the quality of evacuation procedures and cost to operate are considered.

ferry design by sea transport

The conclusions found in Baird’s study were that:

  1. Efficiency:
    The catamaran was found to have a smaller block coefficient1 and, due to significantly lower resistance, the catamaran requires less power to perform at the same speed and carrying capacity of a monohull.
  2. Motion Sickness Incidence:
    The catamaran was found to have an advantage over motion sickness thanks to its specifically designed shape which reduces the likelihood of slamming and rolling.
  3. Manoeuvrability and Seakeeping:
    The catamaran’s specific design features, such as its slender bow form and its widely spaced hulls result in a vessel that can operate both in tight areas and in adverse weather conditions. The monohull was found to have a much higher rate of cancellation due to weather and port size.
  4. Safety:
    The catamaran was found to have an advantage over the monohull with regards to its superior safety and evacuation features and its lower environmental impact.
  5. Cost:
    The comparison shows that the catamaran has a considerably reduced operating costs that its monohull competitor and is far less likely to experience cancellations due to environmental factors.

Dr. Baird’s comparison study concludes that medium-speed RO-PAX catamarans offer very good seakeeping, a greater manoeuvrability in port and overall lower operating costs than comparable monohull vessels, making them the ideal choice for operations in the medium-speed, medium-sized ferry sector.
1 the ratio of the volume of the displacement of a ship to that of a rectangular block having the same length, breadth, and draft.

At Sea Transport our team of ferry operation consultants are experts in finding ferry solutions through our bankable feasibility studies and operations management services no matter the transport task and size.

For more information on our ferry operation services, please click here.

To view our ferry fleet, please click here.

catamaran ferry leaving china

T&T Government Purchases New RORO Catamaran

74m catamaran ferry design

Sea Transport Solutions is pleased to announce that the brand-new STS-Designed RORO passenger and cargo ferry dubbed ‘The Galleons Passage’ will be operating the sea route between Trinidad and Tobago after its purchase this past January.

This 74-metre catamaran has an aluminium superstructure comprising a steel hull design, a capacity of 700 people and up to 100 vehicles, a maximum speed of 22 knots and, due to its 2.75 metre draft, it can berth anywhere at the Port of Spain harbour including the ferry terminal without dredging.

The Galleons Passage, whose name was inspired by the route it is set to run of the same name, is expected to arrive from China sometime in mid May, 2018.

catamaran ferry leaving china

Galleons Passage leaving China

Imbert also stated that the new vessel is intended to assist with the sea bridge while the other passenger vessels are drydocked for repairs but did add that the vessel is ‘perfect’ for the Toco-to-Tobago route as that journey will take only one hour.

The naval architects and ship designers at Sea Transport are confident that The Galleons Passage will meet the high expectations held by both the T&T Government and the route’s future passengers.

Fore more information on Sea Transport’s ferry designs, please click here or get in touch with our head office.

fast cat ferry build

Two New Vessels Introduced to Philippines Fleet

Sea Transport ferry builders

The Archipelago Philippine Ferries Corporation (APFC) is responsible servicing and connecting the 7,107 islands of the Philippines through their FASTCAT Ferry services.  Sea Transport Solutions has been an integral part of the ferry service’s growth through building and delivering vessels that are safe, reliable and efficient.

Our point of difference in providing the Philippines with their only Roll-on/Roll-off catamaran service has given APFC an advantage in offering their customers more options in their travel.

fast cat ferry Sea Transport

The reputation of the FASTCAT Ferry Services throughout the Philippines continues to grow due to the company’s unwavering commitment to safety and adhering to international standards when it comes to sea travel.

With more and more people using their ferry service to travel in between destinations in the Philippines, Sea Transport Solutions in partnership with Guangdong Bonny Fair Heavy Industry Ltd, is proud to announce another two vessels have been launched in the APFC fleet bringing the fleet to a total of twelve vessels.

We have no doubt that through their attention to quality, detail and passenger safety that this fleet will continue to grow over the coming years as will our professional relationship with the team at Archipelago Philippine Ferries Corporation.

ferry building by sea transport

Fast Cat ferry design

Raising the Bar in Safety

Fast Cat Ferry

Sea Transport Solutions is proud of be part of the collaborative team that is raising the safety standards for Archipelago Philippine Ferries Corporation’s passenger ferry services. The new motto for APFC, “Ferry safe, ferry fast and ferry convenient”, is based on the firm goal to provide safer, more comfortable and more reliable ferry services to the Philippines.

Archipelago Philippine Ferries Corporation

The APFC has ferry transportation routes that seamlessly connect the 7, 107 islands of the Philippines including the country’s very first new Catamaran RORO (Roll on, Roll Off) ferries.

The focus to improve passenger safety, comfort and welfare prompted APFC to contact Sea Transport Solutions in order to bring the Philippines its first fleet of 10 RO-PAX (Roll on Roll Off Passenger Ship) vessels that were fully compliant with international standards for damage stability, firefighting and lifesaving.

Within the first 2 years of re-fleeting with these new vessels, APFC has run successful operations on both the eastern and western corridors of the country. The key to the success of APFC is centered on time, safety, reliability and positive feedback from passengers, as well as the fact that APFC was bold enough to look at a new and innovative ferry design.

“So far, we have made significant impact on safety and the travel time of people and cargo within the islands because the ferries used are far faster than the second hand-tonnage operating in the country.” Chet Pastrana, Chairman of the APFC.  Sea Transport Solutions has worked as part of the collaborative team to raise safety standards and awareness for the country’s ferry services which was in need of new systems and practices.

“The Philippines has the worst maritime record in the world for a single incident and I would really like to change that stigma that the Philippines does not adhere to safety standards. We’ve initiated a modernisation  program and other ship-owners will follow, and we can be proud that the Philippines is genuinely trying to get away from the perception that we are not responsible ship-owners.”

Chet Pastrana, APFC Chairman

The system put in place by APFC is similar to that of airlines. Through investing in systems such as seat allocation, strict boarding controls and new technology, the company now has complete control over their passenger numbers and aware of the operations on their vessels at all times and in real time. “We want to be able to raise the standard of service and to provide a safer and more comfortable means of transportation,” explains Mr. Pastrana. “We hope Archipelago’s initiatives will encourage other owners to follow its example of safe, modern tonnage.”

“What we are offering is the convenience of daily departures, not having to wait for a container to be filled and not having to wait for it at the port,” says Mr. Pastrana. “Essentially the company is offering a point-to-point delivery of goods and people and there is no multiple handling. It’s a door-to-door service.”

Sea Transport Solutions is proud to be affiliated with assisting companies to improve their systems, their safety, their operations and ultimately their company’s reputation.





Philippines Flag

UCPB Provides Loan for 2 New RORO Ferries

The United Coconut Planters Bank (UCPB) and Archipelago Philippine Ferries Corporation (APFC) have signed a new agreement to finance the purchase of 2 new ROPAX ferries for passenger transport and rolling cargoes, adding to APFC’s 10 ROPAX sister ships which came into service in recent years.

These new Catamaran RORO (Roll on, Roll off) marine vessels will run the Philippines’ eastern route as part of the APFC’s modernisation program that aims to bring in world-class and internationally compliant marine vessels to the country. Currently the APFC services the connection between the country’s 7,107 islands.

These new vessels will ensure greater passenger safety, welfare and overall comfort. The loan will partially finance the acquisition of these new state of the art vessels – designed and built by Sea Transport Solutions in partnership with Guangdong Bonny Fair Heavy Industry Ltd.

STS was in attendance of the ceremonial signing along with Guangdong Bonny Fair Heavy Industry Ltd and executives from UCPB, APFC and CAPP Industries Inc Ltd.