Every day, every hour, bulletproof

Taking the name Thunder Child from the fictional ironclad torpedo ram in H. G. Wells’ The War of the Worlds, this vessel will hopefully not fight Martians, but is ready to set a world record.

This time last year, Polarcus Naila was putting to sea after a rather special and lightning-quick retrofit. The seismic vessel had just been equipped with a brand new solution, twin fin propulsion, so there was an element of going out into the unknown…

Naila is a seismic survey vessel that tows 8 km long streamers to sweep huge areas of the seabed, supplying precious data to oil exploration customers amongst others. It’s a specialist job with a very high daily operating cost that still pays well given the potential oil and gas at stake. But that all depends on uptime and avoiding disastrous downtime through unplanned maintenance and drydocking. As far as the equipment is concerned, failure is not an option.

CONVENTIONAL WITH A TWIST

To solve problems they’d been having with traditional thrusters, and minimize the potential risks in the future, Polarcus looked to a new concept, Caterpillar Propulsion’s twin fin system, with a retrofit that would crucially take as few as 45 days. Suitable even in harsh environments, the tailor-made fins protect the propulsion system from ice and can be fitted with ice knives. Crucially, the fins also give access to all the propulsion mechani­cal parts within the hull profile. In this way, Polarcus would get the cargo space saving and maneuverability benefits of an outboard solution as well as critical reliability gains.

UPTIME, PLUS A WHOLE LOT MORE

But it hasn’t stopped there. With increased thrust – and lower input power – thanks to larger, slower-running, controllable-pitch propellers and minimal mechanical loss, Naila’s diesel-electric solution has also saved massively on fuel and emissions, while improving overall vessel performance. Indeed the surprising improvement in course stability and seakeeping behavior even has an effect on the quality of the seismic data, while the extra thrust means they are looking at carrying extra streamers for even wider and more effective surveys.

AWARD-WINNING INNOVATION

With competitors in their industry left scratching their heads at the uptime and performance gains, the heads of Polarcus, along with the captain and crew of Naila, have been overjoyed with the success of the new propulsion system. But what does the future hold for twin fin propulsion? Winning the recent Technical Innovation prize at the Seatrade Maritime Awards in Dubai confirmed the potential.

With any number and configuration of fins, the system can be applied to newbuilds, retrofits and conversions in any commercial marine application. Indeed, the latest candidates are a number of cruise ship operators who have been blown away by the reliability, fuel efficiency, silent operation and safety advances.For twin fin propulsion, which is now a new verified product within Caterpillar Marine, it seems that the sky, or rather the endless sea, is the limit.

"There’s no luck about it. It’s a world first but we designed it with the statistically most reliable equipment.” - Mattias Hansson, Senior Project/Sales Manager, Caterpillar Marine