MARTY, MINN. – Kurt Krippner climbed onto the shovel of his family's bobcat as his father lifted him to the top of the flagpole they'd planted the day before in their snowy Stearns County farm field. Together, they worked to make sure that a small solar panel and light were set to shine on a growing makeshift memorial to three Minnesota National Guard soldiers who died last week when their helicopter crashed in a nearby tree line.

"We may not know the men, but we're heartbroken for the families," said Krippner's sister, Kristi Kalkbrenner, who fought back tears as she stood amid roses, poinsettia planters and a stained-glass angel at the base of the flagpole. "It hits home that people lost their lives here."

As families and friends grieved privately, Kalkbrenner and the Krippners were among hundreds of strangers who joined ranks Saturday with thousands around the globe to pay tribute to the fallen and support those mourning their loss.

On Thursday, the three men boarded a UH-60 Black Hawk for a routine maintenance test flight and lifted off from the St. Cloud Regional Airport at 1:55 p.m. Nine minutes later, according to emergency dispatch reports, the crew sent a may-day alert. Communication with the aircraft was lost, and local and state emergency workers converged for an intense search-and-rescue operation.

As dusk fell, a State Patrol helicopter with thermal-imaging cameras spotted the wreckage about 16 miles southwest of St. Cloud. Killed were: Chief Warrant Officer 2 Charles P. Nord, 30, of Perham; Chief Warrant Officer 2 James A. Rogers Jr., 28, of Winsted; and Sgt. Kort M. Plantenberg, 28, of Avon.

All were assigned to Company C, 2-211th General Support Aviation Battalion, out of St. Cloud. They had returned in May from a nine-month deployment to the Middle East, where they conducted medical evacuations.

That the men had survived a mission abroad only to die at home seemed especially heartbreaking.

"You worry when they're gone, not when they're back," said Mary Mueller, who was among those volunteering Saturday at the Holy Cross school in nearby Kimball, Minn., to feed those investigating the crash scene.

"At times like this, you feel helpless," Mueller added. "This is something we can do."

'Inherently dangerous'

Inside an airport hangar Saturday afternoon, National Guard officials stood in front of a UH-60 Black Hawk to provide information, albeit sparse, about the crash. Nearby was an empty hangar stall where the copter that crashed would have been parked.

More than a dozen miles away at the crash site, an investigation team from Fort Rucker in Alabama gathered information and evidence. Officials said Saturday it was unclear how long their investigation would take. In the meantime, all UH-60 Black Hawks have been grounded, which is standard procedure during a probe's initial phase. Those helicopters are expected to be back in service soon.

"To come home and have this happen … is the worst thing you can possibly imagine," said First Sgt. Nicholas Arrigoni. "But what we do is inherently dangerous — whether we're deployed or stateside. We will continue to fly, when we're ready."

The Black Hawk that crashed was on a routine maintenance flight, work that is performed almost daily, officials said. As is standard, two pilots — Nord and Rogers — were on board. Plantenberg was a technician mechanic preparing to start flight school.

Officials declined to discuss details of the specific mission or identify the pilot in command.

Their job was to save lives

At Saturday's news conference inside the Guard unit's hangar, those who worked with the fallen soldiers talked about the "devastating loss" of three comrades — men who grew up in small Minnesota towns and joined ranks to serve their country.

"This unit is a medical company and its job is to save lives," said Maj. Nathan Burr, the unit's former commander.

Plantenberg, a biathlon athlete, graduated from Albany Area High School in 2009 and joined the National Guard in 2016 as an electrician.

"He was always winning rowing competitions, CrossFit competitions," Burr said. "He was someone you could always count on to excel to the next level."

His family remembered him as a kind, loving son and brother who was loyal to his friends and neighbors. "It's impossible to envision life without him," relatives said in a written statement.

"We take comfort in our faith, the love of family and friends, and the knowledge that Kort died doing what he loved best: serving his country and pursuing his lifelong dream to be a Black Hawk helicopter pilot."

Rogers, a native of the southern Minnesota town of Madelia, came from a military family — his mother and sister served in the Air Force, Burr said. Rogers graduated from nearby St. James High School in 2010 and enlisted in the Minnesota Army National Guard in 2009. His buddies nicknamed him "Little Known Fact James" because he reveled in sharing tidbits of information with his fellow soldiers.

"He had no limit to his knowledge," Burr said. "Every time you flew with him, you never knew what you'd talk about. ... We always wanted to fight over James for our trivia team."

Nord graduated from Perham High School in 2007 and enlisted in the Minnesota Army National Guard that year.

He was married with a 2-year-old daughter and another baby on the way. When he wasn't flying for the National Guard, he was piloting a helicopter dusting Minnesota cropland.

"He couldn't believe he was lucky enough to fly helicopters while other people went to work in cubicles," said longtime friend Parker Carignan.

As National Guard officials provided the brief media updates, dozens of fellow soldiers dressed in fatigues stood nearby, solemn and stoic.

But for some, the grief was too great as tears welled in their eyes.

"There's nothing I can say that will take away or lessen the pain you are feeling," Maj. Gen. Jon Jensen said. "What I can tell you: You are not alone in your grief."