HST-2 was built as Alakai, which means "sea path" in the Hawaiian language. The vessel is a long high-speed roll-on/roll-off passenger and vehicle ferry. She used to operate a daily service operated by Hawaii Superferry at a speed of between the islands of Oahu and Maui. HST-2 has a capacity of 866 passengers and up to 282 subcompact cars. Alternately, its vehicle decks can be reconfigured in five minutes to carry up to 20 large trucks and 90 cars. Like her sister ship , the vessel features environmentally friendly technologies including non-toxic bottom paint, zero wastewater discharge and clean diesel engines. Hawaii Superferry's vessels were designed and built by Austal USA, a subsidiary of Austal, an Australian company that is the world's largest builder of fast ferries. Construction on HST-2 began in June 2004 in Mobile, Alabama. The ship was launched in January 2007, christened in April 2007 and sea trials went smoothly.
Starting service
The vessel arrived as Alakai in Honolulu, Hawaii on June 30, 2007 with a celebration, after a smooth 17-day delivery voyage. The ship's maiden voyage was on August 26, 2007 and the trip to Maui was smooth. The voyage to Kauai was rougher and Alakai was met by about a dozen protestors on surfboards blockading the entrance to Nawiliwili Harbor. The protestors were peacefully cleared by the United States Coast Guard.
On February 13, 2008, Alakai went into dry dock to make repairs to her auxiliary rudders that were damaged in late January. The dry docking was extended due to hull damage caused when a tugboat moving Alakai into dry dock lost power and collided heavily with the catamaran. Alakai returned to service in early April 2008 shortly after Aloha Airlines ended service. Before resuming service the ship went through sea trials and was re-certified by the Coast Guard.
2009 shut down
On March 17, 2009 after about 11 months in service, the Hawaii Supreme Court ruled that the legislation permitting Alakai to operate without an environmental review was unconstitutional. Hawaii Superferry made one last round trip to allow an orderly return of passengers who were not on their home island. They canceled existing reservations and did not take new reservations. The Superferry company intended to look for other work for Alakai; it had also left open the possibility of bringing the ferry back into service if and when Hawaii completed an environmental review, but the company decided to abandon the vessel ending all possibilities of returning to Hawaii. In January 2010, the United States Maritime Administration announced that Huakai and Alakai would be used to assist with relief in the 2010 Haiti earthquake.
Navy acquisition and name change
On September 13, 2010, Huakai and Alakai were auctioned off, for $25 million each, by the U.S. District Court for the Eastern District of Virginia. They were purchased by the U.S. Department of Transportation's Maritime Administration. On January 27, 2012, the U.S. Department of Transportation's Maritime Administration transferred two high speed vessels, Huakai and Alakai, to the U.S. Navy under the Defense Authorization Act of 2012. The Navy had planned to use the vessels to transport troops and equipment to training areas from Okinawa and other locations, helping the Navy meet the unique operational requirements without the need to build new vessels. In May 2012, the Navy announced that both Alakai and Huakai had been renamed. Alakai was to be named USNS Puerto Rico and Huakai was to be named. Guam was modified to replace the chartered * in Okinawa in March 2013, and Puerto Rico remained laid up until 2016. On August 19, 2012, HST-2 was towed from Norfolk, Virginia to Philadelphia, to keep it safe from hurricanes while future uses for the vessel were being evaluated. On February 5, 2016, the U.S. Secretary of the Navy removed the name Puerto Rico from the vessel. The name Puerto Rico was subsequently reassigned to on December 14, 2016.
On March 24, 2016, Bay Ferries Limited announced that it had reached an agreement with the U.S. Maritime Administration and the U.S. Navy for a multi-year charter of HST-2. The vessel would be operated for a passenger/vehicle ferry service in the Gulf of Maine between Portland, Maine and Yarmouth, Nova Scotia and retain the name HST-2, but the service and vessel would be branded as The CAT to align with previous branding used when Bay Ferries operated a high-speed passenger/vehicle ferry on the same route six years prior. The vessel underwent a refit at a shipyard in South Carolina and the service started on June 15, 2016.
