Presque Isle arriving at Two Harbors (first time on the channel!) to load iron ore on a gorgeous but very windy day! The second thousand footer built for the Great Lakes (1973), and the only true ITB ship still sailing anywhere. The tug was built in New Orleans while the barge was built in Erie, PA. She’s been a rare sight the last couple years! In 2022 she missed much of the season due to a bad, 1 ton engine bearing that needed to be custom built and installed, spending nearly 120 days laid up in Superior. Then in 2023 she again missed much of the season due to 5 year inspections and general maintenance. Hopefully this year she’s able to sail more consistently!
Her unique design and legacy stems from a combination of technical and political reasons. In the early 70s a handful of Integrated Tug Barge ships were constructed in the US, Presque Isle included. These vessels were intended to be as safe and capable as a regular freighter, but take advantage of the legal loophole that allowed tugs to run with fewer crew. The barges were designed as standard ship hulls, minus the pilothouse and engineering equipment, while the tugs were designed solely to serve as the stern end of a larger ship, and only capable of basic sailing and maneuvering on their own, without other tug capabilities such as ice breaking or other utility, and top heavy enough that sailing independently in any sort of wind or waves was risky. The tugs and barges were designed specifically to only be capable with their specific counterpart, and locked together with a very rigid joint, allowing no movement between the tug and barge, essentially making them a single vessel. The tug could detach for maintenance or as a massive lifeboat in emergencies but otherwise sailed as part of the larger vessel.
Unfortunately for the ship builders, the Coast Guard saw these vessels and decided these were not tugs at all, rather a typical freighter that could split into two parts, and thus requiring the full crew needed for a freighter. This made the original intention of design useless with a much higher construction cost, and so production stopped after only a handful were ever built.
The idea lived on however, the Articulated Tug-Barge (ATB) was much more successful and has become a common sight around the US. Featuring the same ship hull, but with a much smaller tug capable of independent operations and more “standard” tug actions plus a more flexible connection between the two vessels. This allowed for the original goal to be met, however the design compromised the ability to sail in harsher environments, and were long constrained to coastal and river use. In recent years a stronger version of ATB have come into use, such as the Great Lakes’ VanEnkevort vessels. They retain the smaller size and versatility of the ATB model but incorporate ITB ideas such as the stronger connection and the tug and barge being specifically designed for each other (granted they can be swapped if redesigned in a shipyard) These vessels are considered modern ITBs in some circles, but they lack many other characteristics that identified them, such as the large ship-like pilothouse.
As for the handful of true ITB ships constructed, most served for many years, mostly for US companies. The last oceangoing one was retired in the mid 2010s, leaving Presque Isle, with her longer lifespan due to the Great Lakes, as the last of these experimental ships.
An extended version of this video (and others!) are available to members if interested!
00:00 Plowing Waves
1:00 Approach & Salute
4:40 Closeup
7:00 Docking
9:25 Prepping to Load
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