What is the primary characteristic of an ITB vessel?

The primary characteristic of an ITB (Integrated Tug-Barge) vessel is a rigid locked connection between the tug and the barge. This design allows for a more stable and efficient operation by creating a single unit that can handle higher sea conditions and improve maneuverability. The rigid connection means that the tug and the barge are effectively locked together, which helps to minimize the movement between the two during transit. This design enhances the overall performance, especially in terms of fuel efficiency and handling abilities, making it preferable for many maritime operations.

In contrast, while a flexible connection might be found in other towing configurations, it does not offer the same level of integration or stability as the rigid locked connection of an ITB. Similarly, a single-unit design without any separation implies a complete integration that might not accurately define the specific characteristics of an ITB, and a combination of both articulated and rigid designs introduces unnecessary complexity that does not align with the standard definition of an ITB vessel.