BELFAST - One of the massive yellow and black things on the Belfast waterfront Thursday was a crane. But you've probably guessed that.

The others, according to James Harkins, project manager for Keeley Crane Service, are dock fenders built specifically for a nuclear submarine. 

The fiberglass shells of the school bus-sized (and colored) bumpers were fabricated in Augusta by Kenway Corp. then brought to Belfast for assembly at Front Street Shipyard during the past month, Harkins said.

Kenway specializes in composites, a broad category of reinforced resins that includes fiberglass. The company's president and CEO, Kenneth Priest, is a partner in Front Street Shipyard and the businesses have cooperated on projects in the past including a line of composite-hulled motorboats.

Each of the fenders weighs 112,000 pounds with much of the weight coming from concrete poured into the forms as ballast, Harkins said. The load tested the upper limits of the 275-ton-capacity crane, he said (if that math doesn't seem right, Harkins said the extension of the the boom factors in the capacity of any particular lift), but wasn't out of the ordinary for the Portland-based company.

"This is another day at the plant for us," he said.

Harkins said the fenders will likely be in Belfast for another day before heading to Groton, Conn., the self-proclaimed "Submarine Capital of the World," where Harkins said he believed they would be used for a Trident nuclear-powered submarine.

If you dont get a chance to see them, don't worry. The fenders loaded on Thursday are reportedly the first of four shipments — eight fenders in total — that will pass through Belfast.

Ethan Andrews can be reached at news@penbaypilot.com