We’re surrounded by software everywhere, and the shipping industry is no exception. As the use of software on board vessels is increasing, so too are the risks associated with it.
Two redundant GPS systems on a rig failed simultaneously. The software did not detect this failure, and consequently the dynamic positioning system changed the rig’s position by 70 metres. The drill string was cut and the rig was out of operation for several days, resulting in considerable financial loss.
This is just one examples of software failure leading to serious consequences.
DNV, yards and suppliers are therefore working together to reduce anticipated future risks in a joint industry project – the Safe Maritime ICT project – creating guidelines for the development and assessment of critical software intensive systems on board vessels.
Software everywhere
“You must realise that what you do with a click on the PC screen is not a game – it is reality,” states graduate engineer Reinert Giere, the head of Meyer Werft’s Electrical and Control Engineering Group at Papenburg in Germany. He is in charge of a staff of 30 that are responsible for all the electrical systems on board the ships built. Generators, electrical distribution and propulsion systems, automation, navigation – and the integration of all these subsystems into the ship’s network.
“There is software everywhere on the ships we build. So it’s even more important that the software is correct and robust.
We don’t programme it, but we stipulate the requirements for how it should be programmed,” explains Mr Giere. “We describe verbally what we want the systems to do and stipulate input for different needs.”
Meyer Werft believes this project is important because it sees the importance of finding possible failures in advance.
“Our key persons at the Meyer yard have knowledge and experience gained from all our former built ships, but it is important to have other people’s experiences too,” says Mr Giere. “This especially applies to errors relating to ships that have been in operation for many years. As a yard, we often monitor the ship very carefully the first year, but often it is only the shipping company and manufacturer of the plant that know what takes place after that. This is often difficult to find out, since they often keep this information to themselves.
However, in this project we share our experiences so that we can all improve.”
Laborious process
Mr Giere describes the laborious process to ensure software quality that is carried out at present. First of all, there is a factory acceptance test at which the owner, DNV and others are present. The next phase is to test all the systems together to see how they will act in real life.
“During these tests, we also try to simulate errors to see what happens,” says Mr Giere, who admits that they are often surprised, during both the acceptance test and the end test, when fundamental problems which should not arise nonetheless do so.
“The sub-suppliers are not always aware that they need to look upon a ship as something different from a land-based facility. At sea it is passenger safety that counts. We discover some errors at the yard, but the ship and its many IT systems are really tested during the sea trials – especially in poor weather conditions. That’s not a desirable situation. It’s important that those designing the plants are aware of the errors that may arise. The software must be adapted to the environment in which it is used. That means a higher work load during the design phase, but finding possible failures in advance also means fewer errors during the sea trials and the first year of operation.”
Cruise ships – more complex systems
Cruise- and LPG/LEG-companies are Meyer Werft’s main customers, and the yard will shortly be delivering cruise ships to NCL, AIDA, Celebrity and Disney.
“The customers want the most modern systems and have increasingly bigger plants, more complex systems and more integration,” states Mr Giere. “Integration is sometimes difficult, and it is especially difficult to integrate while also making sure there are no hidden failures.”
Mr Giere underlines the importance of having IT built up so it can be operated intuitively. It is important – especially on cruise ships – to know how the system can be operated if the IT is not working. This is why the cruise company personnel monitor the building of the ships carefully and also learn a lot during the three-month period in which the systems are started up and tested. During this time, the focus is on knowledge transfer and sharing.
Having worked for Meyer Werft for 15 years, Mr Giere cannot think of a better place to work.
“It’s rare today to be allowed to help build something from scratch where you see the product taking shape. It’s a good feeling to see the whole product and know you have been part of the entire process.”