Seismic vessel control station enhanced by simulator training

The marine seismic industry has seen enormous changes during the 1990s, and the rate of change does not abate. As vessels become ever larger, the number of streamers increases and streamer separations grow wider, crews are continuously challenged to cope with the added complexities of acquisition work on a greater scale. The potential hazards have never been greater.

Schlumberger Geco-Prakla's newest vessel, Geco Eagle, has unprecedented levels of new technology on board. This has led the project team to seek additional training in advance of the vessel's launch.

As part of the safety design, a "hands-off" approach was adopted to ensure minimum handling of equipment during deployment and retrieval. Geco Prakla Marine Technical Manager for North and South America, Carel Hooykaas, explains: "The key to much of the new technology on board Geco Eagle is the streamer control station, which is situated in a prominent position overlooking the back deck. This position enables control of all in-sea equipment, streamer reels, conveyance systems, and monowings (steerable deflectors) from one central point.

"Multi-functional displays and joysticktype user interfaces provide the means to interact with the massive streamer spread. From here, streamers are deployed, recovered, controlled, and tested, eliminating the need for personnel to be present in the instrument room during the process. Communication with the rest of the vessel is also done directly from here."

Simulator

"Since so much of the new technology is actually controlled from here (station), we decided to develop a training simulator to bring crews up to speed with the technology before they even set foot on the vessel," explains Hooykaas "The system is similar in principle to a flight simulator, replicating the onboard environment including the control chair, user interfaces, alarm panels, and the CCTV system.

A projection system and 150° curved display screen are used to create a virtual version of the Geco Eagle back deck.

"We were fortunate to be able to find a product that was essentially 'off-the-shelf' in terms of the hardware requirement. We had to adapt the software quite a bit to tailor it to our own requirements. Obviously, all of our own peripheral equipment in the instrument room and winch controls has had to be interfaced with the system."

Tor Eilertsen is the Party Manager responsible for implementing the simulator training. "Our first priority was to train crews on backdeck procedures and best practices during normal deployment and recovery operations" he says, "but the simulator also enables us to provide experience with uncommon situations. For example, we can test an operator's reactions where the operation is going outside the parameters of safe towing. Vessel speed, turning rate, wing control, and streamer depth control can all be varied, as can weather conditions. And, even for basic training, it's very helpful to be able to play the session back to point out how a situation was handled and what deviations from procedures were taken."

Exercise

The simulator exercise starts with one or more streamers in the water. Based on the currents and waves, the streamer position is calculated. This data is then fed into the navigation and positioning system, which will in turn display the streamer depth and shape based on these calculations.

All other instrument room equipment is also simulated, while the view of the back deck is projected onto a large curved screen. This is realistic enough to include people walking around on the back deck attaching birds to the streamers as they are deployed.

"The instructor can then change variables such as current and wave strength and direction, or introduce obstructions forcing the vessel to turn" explains Eilertsen. "It's even possible to introduce faults in the streamers, causing earth failure for example," Eilertsen said.

Initial training is complete and the Geco Eagle is now at work offshore Brazil. Mick Richardson, the vessel's manager, said "The simulator provided for smooth start-up and achieved high levels of daily production with ten streamers right from the beginning. Much of this success can be attributed to the fact that the crew had been well trained in the use of the technology which they were to apply when operations began. Although it is difficult to quantify exactly how the training simulator helped, I can say that we experienced no operational problems with equipment covered by the training programs, which must be a good indicator."

"The simulator has given the crew field experience to which they would seldom be exposed otherwise. This has enhanced their operational awareness, enabling us to build controls around clearly identified high-risk operations and thereby reducing the possibility of accidents."

The training simulator will continue to play an important role, not just for the Geco Eagle, but for other vessels that will be fitted with streamer control stations in due course. The software element is fully portable, enabling it also to be used on board vessels to give further training as necessary.

Since the towed equipment is common to the whole Geco-Prakla fleet, there are also plans for crews of other vessels to undertake operational seminars using the simulator, and integration of the maritime bridge crew's role is currently under evaluation too.

In the meantime, the simulator is being used to develop and build the streamer configuration for the first twelve streamer job and to train the crew of Geco Eagle to handle that job, scheduled for autumn 1999.