The Schofield Barracks Black Hawk was just a mile and a half out of Forward Operating Base Payne on a night rescue mission April 19 when Afghanistan’s unforgiving conditions snatched the chopper out of the sky and claimed the lives of its four Hawaii-based soldiers.

There were thunderstorms in the southern Helmand province area, and several miles of visibility quickly dissolved into a blinding and disorienting curtain of wind and dust.

The two pilots, Don C. Viray, 25, of Waipahu, and Nicholas S. Johnson, 27, of San Diego, both chief warrant officers, had their night-vision goggles on, but had to take them off because they lost what little light was available to make them work, said Johnson’s father, Robert.

"Basically, they just couldn’t see anything," he said.

The Black Hawk was flying low and fast at 750 feet when a phenomenon known as "spatial disorientation" occurred, he said.

The spinning or dizziness that comes from the sensory illusion of not being able to determine aircraft and body position in relation to the ground or sky is the No. 1 killer in Army aviation, according to the service.

"They say it’s the same as being silted out if you are a diver," Johnson said. "You don’t know what’s up, what’s down, what’s left, what’s right."

According to a study published in August in Aviation, Space and Environmental Medicine, from fiscal 2002 to 2011, 31 percent of all fatal Army helicopter accidents were related to spatial disorientation.

A witness reported seeing the helicopter flying in a downward angle before it hit the ground and exploded in a fireball, said John Workman, whose son, Sgt. Chris Workman, 33, from Boise, Idaho, also was killed.

Sgt. Dean Shaffer, 23, of Pekin, Ill., was the fourth crew member to perish.

The Army recently briefed the families on the investigation and released the report, leaving some questions lingering as the families try to pick up the pieces.

Robert Johnson and John Workman spoke about the crash and provided the details of the investigation.

The 25th Infantry Division at Schofield said the Star-Advertiser would have to submit a Freedom of Information Act request to obtain the report — a process that sometimes takes the military up to a year to fulfill.

Both pilots were experienced, Johnson said.

"Our take on it is they were operating as a unit, they were all disoriented, there was a tragic crash and we blame no one," he said.

According to the investigation, the Black Hawk was flown into the ground as a result of pilot error, Workman said.

"Evidently, Don (Viray) was flying and Johnson was co-pilot, but he wasn’t flying," he said.

But Workman questions the conclusion of the report. There were reports of gunfire in the area, he noted.

"There are several reports of seeing a flash, a tracer flash, that’s what it (the investigation) is saying, from the ground and then two or three seconds after that, a major fireball," said Workman, who lives in Idaho.

The Army, however, could find no sign of enemy activity around the base, he said.

"I don’t know that they can 100 percent prove that (it was pilot error)," he added. "The whole craft burned up. The accident happened about 9:30 (p.m.), quarter to 10, and it burned for hours."

Johnson also noted that the Army investigation found no evidence of the chopper being shot down.

"I’m not a pilot, I don’t have the expertise to question that, and I wish I did," said the California man. "So I have to believe what the Army is telling us and basically, they said that they hit bad weather, they couldn’t see and it was a collision with terrain."

The Black Hawk, acting as gunship support, was to link up with a medevac Black Hawk on a mission to assist Afghan police who had been injured by a suicide bomber, Johnson said.

He said the medevac helicopter took off from another base.

"The weather prevented (the rescue) and both medevac and escort gunship were forced back and the medevac made it back and Diamond Head 20 (the downed chopper) didn’t," he said.

The crash was the first loss of life for the 2,600 soldiers of Schofield’s 25th Combat Aviation Brigade on a yearlong deployment to Afghanistan that is now more than half over.

That crash was followed by a second Schofield Black Hawk that went down on Aug. 16 northeast of Kandahar, killing the four-man Hawaii crew, two Navy SEALs, a Navy explosive ordnance disposal technician, and four Afghans.

Schofield Barracks said the investigation into that crash is ongoing. The Black Hawk was operating in support of an assault on the ground, but initial indications were that it was not shot down, the Associated Press reported.

Chris Workman leaves behind a wife, Camille, and a stepson, Cole Hayes, in Hawaii.

"He loved the Army. It just fit his personality and the challenges of it," his father said. His son was going to be a "lifer" in the service, he said.

"He wanted to do everything he could to advance his career and he was trying to get into officer training. I’m sure he’d love to have been a pilot if he could have been, and I’m sure he could have been with enough time under his belt," he said.

Thousands of people turned out for Chris Workman’s funeral in Idaho.

"It was amazing," he said. "Very humbling."

Nick Johnson also was married, with a 1-year-old son.

He had been in the military since he was 18, first in the Navy and then in the Army.

Robert Johnson said he and his wife are coping "as well as we can be after losing our son."

"It never goes away, and it never will," he said, "but we’re comforted in the fact that all four of those men died a hero, trying to help somebody."