KAHULUI, Maui — With three blasts from its horn, Hawaii Superferry's Alakai pulled away from Pier 2C at Kahului Harbor at 11:15 a.m. today on what could be its final voyage in Hawaiian waters.

As the 350-foot, high-speed vessel maneuvered toward the harbor entrance, passengers and employees crowded the outer decks and waved aloha while a tugboat sprayed water into the air in a traditional maritime tribute.

Among those aboard Alakai were Superferry President and CEO Tom Fargo and former company chief John Garibaldi.

Including employees, the Alakai sailed from Honolulu to Maui with 290 passengers and 84 vehicles. The return trip carried 398 passengers and 126 vehicles. The vessel is capable of carrying 836 people and 230 autos.

Passengers expressed sadness and anger that the ferry would no longer be in service for the foreseeable future after Monday's Hawaii Supreme Court ruling that a state law allowing the vessel to operate while an environmental study is under way was unconstitutional.

Duane Meyer, 38, of Haiku, Maui, said he used the ferry on a weekly basis to transport his souped-up 1965 Ford Mustang to car shows. He said he'll have to ship his prized car back to Maui on a Young Brothers barge at four times the cost of using Superferry.

"This is stupid. They should let the people decide and not some stupid judges," he said.

Holding tears back while directing cars into the vehicle check-in area at Kahului Harbor, port utility operator Corrine Dutro-Ponce planned to join fellow employees on Alakai for the final sailing. "It's like a death," she said of the company shutdown.

Dutro-Ponce joined Superferry in its early days in July 2007 and witnessed the company's ups and downs through a four-year legal battle that resulted in Monday's ruling.

"It was hard but we stuck it out and we always had hope we would survive, and we still have hope that it will start again," she said.

Alakai is expected to arrive in Honolulu around 2:30 p.m.