Two female officers reported to the Pearl Harbor submarine USS Mississippi in December — marking the first time women have served on an attack submarine in the Pacific.

The two are a nuclear-trained submarine officer and supply officer, with a third female expected to report aboard “shortly,” the U.S. Pacific Fleet submarine force said.

Later this fiscal year a trio of female officers is slated to become part of the crew of the USS Texas at Pearl Harbor, the Navy said. Both the Mississippi and Texas are newer Virginia-class submarines with crews of about 140 sailors.

Chief of Naval Personnel Vice Adm. Bill Moran spoke to sailors Thursday during an “all-hands call” at Pearl Harbor, and was planning an overnight stay at sea aboard the Mississippi.

The fact that two women recently came aboard the sub was coincidental, but Moran said it gives him the opportunity to see a newly integrated crew on the job.

“It’s heartwarming to know that the barriers to service in places and units that once prevented women from serving, it doesn’t exist anymore,” Moran said after the all-hands call. “I think that’s wonderful.”

The Navy is starting to incorporate women on smaller Virginia-class subs after female officers began serving on big ballistic-missile and guided-missile submarines — including in the Pacific — in late 2011, according to the Navy.

The further sub integration comes as the Pentagon reviews plans by all four services to allow women in all combat jobs. Moran said potential female SEALs would have to meet the same grueling selection regimen as men.

“Absolutely,” he said. “Exactly the same.”

“We haven’t been given an execution date yet by the secretary, so the secretary of defense is still looking at all of the recommendations from SOCOM (Special Operations Command) and all the services,” Moran said. “We will be given an implementation date. We have an implementation plan, and when we’re told to execute, we will execute.”

The Navy said more than 100 female officers have joined the submarine force. Additionally, on Jan. 21, 2015, the Navy began accepting applications for enlisted women on submarines.

Berthing and bathrooms are issues the service has to contend with in cramped quarters. The Navy said the larger Ohio-class ballistic-missile and guided-missile subs were the best starting point. An Ohio-class submarine is 560 feet long versus a Virginia-class sub at 377 feet. Older 362-foot Los Angeles-class subs, which are slowly being retired, are not being considered for integrated crews, the Navy said.

Guided- and ballistic-missile subs have rooms that female officers share. On the Mississippi and Texas, a three-person living quarters will be designated for females, and a sign will be used to indicate whether a bathroom is being used by a male or a female.

For future female enlisted submariners, the Navy has plans for three nine-person bunkrooms, with the aft, or back, crew’s bathroom to be split to create one female-only bathroom and a single-person bathroom for males or females, the Navy said. The forward bathroom would be expanded for males.

The Navy, in a “frequently asked questions” section on enlisted women in submarines, also said “hot-racking” — when three sailors share two bunks — is very common on Los Angeles- and Virginia-class subs because there are not enough bunks for the entire crew, while the practice isn’t as common on the bigger Ohio-class guided-missile and ballistic-missile submarines.

In January 2015 three female officers reported aboard the Virginia-class submarine USS Minnesota in Groton, Conn. The USS Virginia also was chosen as an East Coast sub for integration.

Submariners on all-male crews have been known for some crude humor. Moran said he is not a submariner and can’t speak to that, but he did say they “are a highly professionalized force — and part of being a professional is treating people with dignity and respect. And if there are cultural aspects of being a submariner that don’t comport with professionalism — male and female — then I’m sure they are going to figure out a way to get rid of those cultural barriers.”

Moran said he has talked to some females who served on integrated ballistic-missile subs, “and their feedback to me has been very positive.”

But in an embarrassment for the Navy, male sailors on the ballistic-missile submarine USS Wyoming out of Kings Bay, Ga., were found to have secretly filmed female crew members showering onboard. Ten crew members were punished, with some receiving prison sentences.