Atlantic Spruce is shown at work coming alongside the bulk carrier Oakglen. Atlantic Spruce is steaming stern-first to come alongside the ship. The pilot wanted the tug power near the stern of the ship to assist in turning it, but the ship's stern is cut in, and the tug's bow would be wedged under the stern if she had approached bow forward.
The advantage of the ASD type tug is evident here. She can steam at almost full power in the astern configuration and connect up with her wire as close to the stern as needed.