Southwest Airlines President Tom Nealon marked the carrier’s debut of over-water service to the isles with a promise that “we’re in it to win it.”

The discount carrier’s inaugural flight, appropriately numbered 6808, came from Oakland International Airport to Daniel K. Inouye International Airport on Sunday. The 175-seat plane carried approximately 165 passengers — a robust 94 percent load factor indicating that demand was high.

The jet arrived in Hawaii without a hitch, completing a historically significant weekend for the company. On Saturday, Southwest reached a long-awaited “agreement in principle ” with its mechanics union that finally could bring an end to more than six years of bargaining.

Southwest has maintained that Hawaii is this year’s focus and priority; however, the agreement eases some of the carrier’s logistical tensions. In recent weeks a protracted labor battle as well as the Federal Aviation Administration’s Wednesday grounding of 737 Max jets had strained resources.

Nealon said the labor dispute was “very, very difficult,” resulting in millions in lost revenue as the carrier was forced to cancel a significant number of flights over the last two weeks.

“Typically we have 14 to 15 of our 752 aircraft out of service, and we can make up for that. But we had 40 to 60 out with the mechanics issue, and that’s hard for us,” Nealon said. “I felt really good last night when I learned we have an ‘agreement in principle.’”

Southwest flew to Hawaii on a Boeing 737-800, but the carrier has said that it plans to eventually upgrade its Hawaii service to Boeing 737 Max 8 jets. Nealon said the grounding definitely won’t factor into the company’s first or second launch of Hawaii service, and he doesn’t expect it would affect future expansion.

The 737 Max 8 and Max 9 planes have come under scrutiny since the March 11 fatal crash of Ethiopian Airlines Flight 302. That 737 Max 8 crash was preceded by the October crash of a Lion Air Boeing Max 8 plane in Indonesia.

The abrupt FAA order was a particular worry for Southwest, which has 34 Max jets — more than any other U.S. carrier — and has plans to dramatically expand its fleet of the more fuel-efficient, quieter planes. In comparison, the only other U.S. carriers that fly either the Max 8 and Max 9 jets are American, which has 24, and United, which has 14.

Nealon said Southwest remains confident in its Max 8 jets, on which the carrier has completed 88,000 flight hours over 41,000 flights.

“Whatever is required, we’ll go through that process. We won’t take shortcuts. I’d like to think it’s not a long-term issue,” Nealon said.

Regardless, “it’s not a Hawaii issue,” Nealon said.

The major issue facing Southwest’s Hawaii entry had been the government shutdown, which delayed regulators from completing the carrier’s certification and caused service to launch a month later than anticipated.

Southwest is now making up for lost time. By the end of May, Southwest already will have added 12 daily trans-Pacific flights to and from Hawaii and 16 interisland flights — adding 1,800 interisland air seats and 2,100 trans-Pacific air seats daily to the Hawaii market.

Nealon said the service also fills a long-standing gap in Southwest’s coverage, which didn’t extend to Hawaii — a favorite beach destination for the carrier’s California market.

“Our customers wanted us to fly to Hawaii,” Nealon said.

Erie, Pa., natives and big Southwest fans Tim Klan, wife Holly and 10-year-old son Mark had been tracking Southwest schedules since the carrier announced last year that it planned to start flying to Hawaii.

“We’ve been waiting for this. There was a feeding frenzy. This (Oakland-to- Honolulu) flight sold out in an hour, but we managed to snag $99 flights each way,” said Tim Klan, whose family has been on 30 of the carrier’s inaugural flights.

The family has been on 700 Southwest flights since the couple first booked the carrier in 2001. They’ve also visited each of the more than 100 destinations that Southwest flies.

The Klans said they’ve already booked flights to return when Southwest starts service between Oakland and Maui on April 7. They’ve got tickets for when Southwest begins flying between San Jose and Honolulu on May 5, and they’ll be back when it launches service between San Jose and Maui on May 26.

They’re also coming to Hawaii for Southwest’s April 28 start of interisland serv­ice, which will run four times daily in each direction, between Honolulu and Kahului. The Klans are back again May 12 when the carrier will begin service between Honolulu and Kona flying planes four times daily in each direction.

Southwest has said that it will announce service between Hawaii and San Diego and Sacramento, and interisland service to Lihue in the “coming weeks.”

Southwest’s debut was a big enough deal that Gov. David Ige welcomed the first Southwest jet to the isles. Ige said the launch was the culmination of 10 years of courting by the state followed by a three-year, public-private partnership. It will “improve the state’s economy” and “give customers more options,” he said.

To fill planes quickly, Southwest kicked off its Hawaii service with introductory low fares offering trans-Pacific flights for as little as $49 each way and interisland sales from $29. Southwest’s introductory fares won’t last forever, but they’ve already meant lower fares to and from Hawaii as other carriers, mainly Alaska Airlines and Hawaiian Airlines, have responded to the increasingly competitive environment.

Alaska Airlines spokesman Daniel Chun said Alaska is the leader in the number of routes and flights from the West Coast to Hawaii and for the last seven years has offered the lowest average fares to Hawaii from West Coast origins.

Chun said Alaska is advertising website flight deals from as low as $139 each way.

“Because of our low fares and remarkable service, we’ve grown from 6 percent of the industry’s West Coast departures to Hawaii in 2008 to 30 percent today,” Chun said in a statement. “We’re committed to growing with this community.”

Hawaiian Airlines has had a monopoly in the interisland market since the 2017 shutdown of Island Air and offers nonstop flights to Hawaii from 12 mainland gateway cities, and soon to be 13 with Boston — more than any other carrier. It’s not going to give up its strongholds easily.

Hawaiian announced Thursday that it would add a third daily flight between San Francisco and the Hawaiian Islands in October using new Airbus A321neo aircraft. That announcement followed a dramatic drop in interisland fares to Maui starting in April when Southwest is supposed to start flying there.

Hawaiian Airlines spokesman Matthew Brelis said in a statement Sunday, “We offer the best value in the marketplace. We provide an unparalleled combination of hospitality, choice, comfort, knowledge of these islands and leading punctuality, all of which are supported by a robust schedule of neighbor island frequencies. We will continue to focus on being the best hosts we can be to our guests.”

Southwest only has economy-class seats. Still, Nealon said the Dallas-based airline would ensure that passengers to and from Hawaii “feel cared for and appreciated” without ever charging bag fees or change fees.

“We are in this for good,” he said.