An Honor Flight that took 22 World War II veterans from Portland to Washington, D.C., on Saturday was much like the 32 others that organizer Joe Byron has led.

But, he said, it’s a routine that never grows old.

“It’s a day of just ‘thank-yous,’ all day long,” Byron said of escorting the Maine veterans to monuments in the nation’s capital. “It’s incredible to watch, from young children all the way up to the age of the children of World War II vets whose parents have passed away, they all come over and say ‘thank you’ to the vets. I wish I could articulate what the day means.”

Saturday’s Honor Flight was the second from Maine, following a trip in April 2013. Thirty others have originated from either Boston or Providence, Rhode Island, in the five years that Honor Flight New England has been operating, said Byron, of Hooksett, N.H.

Honor Flights began in Ohio in 2005. Byron said he got involved when, as a police officer in New Hampshire, he was assigned to a unit handling crimes against senior citizens.

Too many seniors never report crimes when they’re victims, Byron said, so he took to visiting a local shopping mall in the morning, when senior citizens walk inside for exercise. He was struck, he said, by how many World War II veterans lived in the community, but also by how many were dying. After retiring, Byron looked for a way to help them.

When he heard about Honor Flights, he said, he formed a New England branch in 2009.

The veterans – primarily from World War II, but terminally ill vets from other wars can also take part – are flown to Baltimore-Washington International Airport and then taken to D.C. to see memorials. This year, that meant a trip to the memorials for World War II, the Korean and Vietnam wars, monuments to the Navy and Air Force, the Iwo Jima Memorial and the Tomb of the Unknowns at Arlington National Cemetery. The trip also included visits to the Lincoln Memorial and the Smithsonian Air and Space Museum, Byron said.

Byron noted that the number of living World War II veterans is dwindling rapidly and he doesn’t want the vets to think the country is forgetting them.

“It’s a race against time,” he said, adding that, for many of the vets, it will likely be their last trip to the nation’s capital.

Byron said that family members who accompany the veterans say they learn more about their service while on the trip.

He said the veterans freely swap war stories with other vets, but World War II vets are known for being reluctant to open up about their war experiences with their own families.

The trips for the veterans are free, but each is accompanied by a volunteer who pays his or her own way.

Despite the cost of about $400, Byron said, there’s no shortage of people wanting to go with the vets to see the memorials.

This year, that group of volunteers included Rick Leighton, who last year went along with his father, Richard Leighton, a Vietnam War veteran who had been diagnosed with terminal cancer.

Richard Leighton, of Westbrook, wanted to see the name of his brother, Raymond Leighton, on the Vietnam Veterans Memorial wall listing those killed in Vietnam. He said it was an item on his “bucket list” of things to accomplish before he died.

Rick Leighton said he had told his father that “come hell or high water, I would get him there.”

Then he learned about Honor Flights and was able to get him on the April 2013 trip from Portland.

In an emotional highlight of the trip, Richard Leighton was able to lay a wreath at the Tomb of the Unknowns with his brother’s name on the ribbon and was also able to see his brother’s name on the wall. Rick Leighton made a rubbing of the name for his father.

Richard Leighton died two months after the trip.

Rick Leighton said he was quick to step up to volunteer for this year’s Honor Flight.

“In memory of my dad, I said it would be an honor to escort a World War II vet,” he said.

As for Byron, he said “each trip is a lesson in humility.”