The 500-Tug Milestone: How a Naval Partnership Is Reshaping Tugboat Tech

From Diesel to Dual-Fuel: A Nautical Evolution

When Robert Allan Ltd. and SCHOTTEL notched their 500th collaborative tug build—a vessel destined for KOTUG Canada at Turkey’s Sanmar shipyards—it wasn’t just a number. It marked a leap in maritime innovation. The milestone tug, an RAsalvor 4400-DFM, is the world’s first large dual-fuel methanol escort tug, designed for Canada’s Trans Mountain Expansion Project (TMEP). This isn’t just another boat; it’s a prototype for cleaner, more efficient port operations.

“The 500th vessel isn’t just a celebration—it’s proof that partnerships can drive technological leaps,” says a SCHOTTEL engineer.

Power Meets Precision

The tug’s specs read like a wishlist for port engineers: two SCHOTTEL SRP 710 RudderPropellers delivering over 120 tonnes of bollard pull, paired with the SYDRIVE-M hybrid system. The latter slashes fuel use and cuts underwater noise—a win for both operators and marine ecosystems. Since 2000, over one-third of Robert Allan’s azimuth tug designs have relied on SCHOTTEL propulsion, spanning models like the nimble RAscal, the robust RAstar, and the versatile Z-Tech series. These tugs range from 18 to 65 meters, with bollard pulls stretching from 20 to 125 tonnes, proving scalability without sacrificing performance.

Why This Partnership Works

Executives from both firms highlight trust and technical symbiosis. “SCHOTTEL’s propulsion integrates seamlessly with our hull designs,” notes a Robert Allan project lead. The collaboration ensures optimal maneuverability—critical for tight port spaces—while simplifying mechanical installations. For operators, that translates to fewer downtime hours and more predictable costs.

As the 500th tug prepares for Canadian waters, it’s clear: this isn’t just about building boats. It’s about redefining how they’re powered, one partnership at a time.