BALTIMORE — For three decades, the late journalist Rob Hiaasen devoted his nights and weekends to crafting a “float plan” — the nautical term for a written itinerary for a journey taken by water. When a boat goes missing, a float plan guides the people left behind on the steps they should take to recover the captain and crew.

Hiaasen, 59, who was gunned down June 28 along with four co-workers in the Capital Gazette newsroom, thought he was writing a novel, a fictional love letter to the city of Annapolis and to the people he cherished — in particular, to Maria, his wife of 33 years. He didn’t realize he was creating a kind of float plan in reverse, a manual that could rescue not him but his family.

The resulting novel (titled not coincidentally “Float Plan”) was released Saturday by Loyola University Maryland’s Apprentice House Press. Proceeds will be donated to Everytown for Gun Safety, an advocacy group that aims to build safer communities by ending gun violence.

The million and one decisions involved in shepherding “Float Plan” through production also provided Hiaasen’s wife and children with a clearly defined project to tackle in the rudderless weeks following his death. The editor and columnist had dreamed all his life of becoming a published novelist. Now, his family could help him accomplish his goal.

“This book,” Maria Hiaasen said, “is what’s been keeping me afloat.” She laughed a little, then said, “We’re back to that title, ‘Float Plan.’ Rob strikes again.”

The novel tells the story of a sweet-natured, feckless high school algebra teacher named Will Larkin. In one disastrous year, Will loses his marriage, job, boat and basset hound while watching his father gradually succumb to Alzheimer’s disease. But just when Will is most adrift, he meets the human equivalent of a buoy — the vet tech Parker Cool.

“Float Plan” is a rueful smile of a book that acknowledges that human frailty is the source of comedy by exploring, for instance, what might motivate an otherwise rational man to attack his neighbor’s gazebo with a chainsaw.

“This book is a tremendous burst of sunshine for Rob’s whole family,” the author’s older brother Carl Hiaasen said. “His voice, his wit, his way of looking at the world, everything that made Rob such a warm and luminous presence — it’s all there.”

Maria Hiaasen said her husband had been writing “Float Plan” on and off for a decade. He submitted various drafts to several publishers over the years without success.

She works as a teacher, and in the novel’s foreword, she describes the Saturday morning routine in the family’s Timonium, Maryland, home:

“As I awoke to coffee and a short stack of high school English papers to grade in the kitchen, I’d hear Rob on his laptop in the living room, tapping out his narrative,” she writes. “He seized and used creative writing opportunities when and where he found them.”

Hiassen filled moleskin notebooks with notations about his characters, which he left on his bedroom nightstand, in his briefcase and in his car. Occasionally, he’d become frustrated with his inability to publish “Float Plan” and put the novel down for months at a time, only to eventually resume tinkering.

Apprentice House, Loyola’s student-run publishing company, originally took a pass on “Float Plan” because the press specializes in nonfiction. But several of Hiaasen’s newspaper columns were published after the shooting, and they prompted Apprentice House director Kevin Atticks to take another look at the novel. He said he concluded that “Float Plan” “is a long-form example of the writing that endeared so many readers to Rob’s columns.”

A collection of those columns also is being planned for release later this year.

‘Fearless about opening himself up’

Hiaasen loved being a journalist, but fiction was his favorite literary form. As far back as 1989, he wrote in a journal he was keeping for his then-infant son, Ben:

“This preoccupation of mine to be a novelist haunts me. It preys on my insecurities as a writer.”

By “insecurities,” Rob Hiaasen partly meant that he feared he lacked the discipline to complete a novel — a project requiring a huge investment of time and effort, accompanied by the high likelihood of rejection. But his self-doubts also were fueled by comparisons between his career and his elder brother’s stratospheric success.

“Let’s be honest,” Maria Hiaasen said. “It’s tough to be the younger brother of a famous writer.”

Carl Hiaasen, a longtime columnist for the Miami Herald, would be a difficult act for any aspiring novelist to follow.

His two-dozen adult novels (mostly humorous crime fiction) debut regularly on the New York Times bestseller list and have been translated into 34 languages. One novel, “Strip Tease” was made into a 1996 movie starring Demi Moore. Carl Hiaasen’s first book for children received was a Newbery Honor, and another was long listed for the National Book Award in young people’s literature. Carl Hiaasen co-wrote the lyrics of three songs with famed L.A. rocker Warren Zevon, and he appears frequently on such programs as The Today Show and CBS Sunday Morning.

No wonder Rob Hiaasen once interviewed other lesser-known brothers of famous siblings (including Cal Ripken Jr.’s brother, Billy) for an article published in 1996 in The Baltimore Sun, where he spent 15 years as a features writer.

“You can’t hit or write your way out of a shadow,” he wrote. “It’s better to be yourself.”

The brothers were keenly aware of the shade cast by Carl Hiaasen’s success. In different ways, it penalized them both.

“Rob was a wonderful feature writer and a hell of a reporter, and the comparisons between us were unfair,” Carl Hiaasen said. “I was older, and I got there first, that’s all. Our styles are so different. There’s nothing I could have taught Rob about writing and much I could have learned from him.”

What makes Rob’s writing special, Carl Hiaasen said, was his younger brother’s willingness to expose his flaws.

“Rob’s writing is introspective and personal and vulnerable in a way that my writing is not,” he said. “I admire that enormously. He was fearless about opening himself up.”

As often happens when people hit midlife, Rob Hiaasen eventually became comfortable with who he was — all 6 feet, 5 inches of him. Maria Hiaasen writes that her husband frequently quoted the psychologist Erich Fromm’s famous saying that “the purpose of life is to give birth to yourself.” Rob Hiaasen spent Saturday mornings at his dining room table because writing brought him joy, and that was reason enough to do it — even if his novel never found a publisher.

Hiaasen moved to Maryland in 1993 and fell under the spell of the Pulitzer Prize-winning novelist Anne Tyler. Both like to write stories about offbeat, unassuming people — workers harvesting berries from trees or a strolling violinist who was a veteran of D-Day.

He wanted to get to know Tyler. He wrote her a note requesting that they meet for tea. She said no. Hiaasen kept writing, over a period of years. She declined, over a period of years. But Tyler gradually became struck by her correspondent’s warmth, charm and grace. She changed her mind, and the two became friends.

“The qualities I admired in his fiction were the same ones I admired in his newspaper writing,” Tyler wrote in an email, “close attention to the details of ordinary life, a subtle sense of humor, and above all, a genuine fondness for each and every one of the people he wrote about.”

She continued: “I hope you’ll include in your story a note about how we can all get hold of a copy of ‘Float Plan.’ I’m eager to read it.”

Readers who haven’t met Hiaasen can enjoy Will Larkin’s attempts to work out an equation for his life. But for those who knew Hiaasen, the novel is much richer. Hiaasen was grateful for every drop of affection he ever received, and “Float Plan” is his tribute to his family and friends.

The book’s two main characters bear more than a passing resemblance to Rob and Maria Hiaasen. The author assigned the names of his daughters, Sam and Hannah, to two minor characters, while Maria Hiaasen said that the couple seriously considered “Will” as a name for their only son before deciding that they preferred Ben.

Mrs. Chisholm makes an appearance, and Maria Hiaasen said that Will’s friend Mack is modeled on Paul Stiff, the best man at the Hiaasens’ wedding. The final page of the novel even contains the subtlest of nods to Tyler.

When Maria Hiaasen wants to remember how much her husband loved her, all she’ll have to do is crack open his book.

“I had to reread the manuscript to write the introduction,” she said, “and it was like Rob was right there in the room. That makes ‘Float Plan’ a priceless work of art for me.”