LIHU'E, Kaua'i — Pilots familiar with the skies over Kaua'i say Friday's loss of a tour helicopter in which three people died appears to be the direct result of flying into severe weather — something an experienced pilot would have recognized and should have avoided.

"It seems to be some combination of inexperience in Hawai'i, which is not insignificant, with what was reported as some significant weather problems. I have flown enough to see how rapidly weather changes," said Brian Alexander, a retired Army helicopter pilot and now an aviation attorney with the New York law firm of Kreindler & Kreindler.

A Heli USA Airways helicopter flew into a thunderstorm off the north shore of Kaua'i that surviving passengers described as a "wall of rain." Pilot Glen Lampton, 43, told National Transportation Safety Board investigators that a severe downdraft pushed the Aerospatiale AS350 from an elevation of 2,000 feet to sea level in a matter of seconds. The helicopter's tail boom hit the ocean about 200 yards from shore before the aircraft lifted up and spun, then hit the water again, flipping over and sinking to the bottom.

"This guy got in over his head real quick. He panicked. He crashed," said veteran rescue pilot Ken D'Attilio, who runs Inter-Island Helicopters on Kaua'i.

While the pilot and all five passengers survived the water impact without significant injuries, three passengers died in the aftermath.

Police said Mary Soucy, 62, and Catherine Baron, 68, friends from Portland, Maine, drowned. Also killed was Laverne Clifton, 68, of Beloit, Wis., who died of heart failure as the result of a near drowning, according to an autopsy performed by Maui pathologist Dr. Anthony Manoukian.

Heli USA vice president John Power said his firm and its pilot are prohibited by the NTSB from publicly discussing the crash.

Lampton had been flying on Kaua'i for less than two months. He told the NTSB he was flying along the north end of the Na Pali Coast when he had to dodge another helicopter. While recovering from the move, he said, his aircraft entered the rain squall.

Surviving passengers Karen and Bill Thorson of Beloit, Wis., have said they remember no evasive maneuver and that the other helicopter was so far below them it looked like a bird.

Yesterday, the pilot of that second helicopter, a Hughes MD500, told investigators that he had seen the storm and turned away. The unidentified pilot was 1,000 feet above ground, while Lampton said his AS350 was at 2,000 feet. The MD500, which belongs to D'Attilio's Inter-island Helicopters, was seen by other helicopter pilots four miles away and headed west when Lampton entered the thunderstorm going east, D'Attilio said.

He said the storm was much too dense for safe flying.

"It was an eighth- to a quarter-mile visibility at best. It did not meet requirements to be able to fly in it — no way, no how," D'Attilio said.

Alexander said visibility is a key factor when approaching weather. "There are some weather systems that you can see and apprise that it's just a light rainstorm. It's got to be a light rain, and you can see the other side. Even then, it's wise to go around," he said.

Several pilots from different companies did see the thunderstorm that day and turned around, The Advertiser learned from talking to helicopter firms on Kaua'i. D'Attilio said his pilot assessed the storm, decided it was too dangerous and turned to fly back the way he had come.

D'Attilio suggested that Lampton, some of whose previous flying jobs have been with the Houston Police Department and a Kentucky television station, is relatively inexperienced by Kaua'i tour-pilot standards.

"He was a new pilot. He had 2,900 hours over 16 years. That's 180 hours a year, and that's not much," D'Attilio said. Many Kaua'i tour pilots fly 1,000 to 1,100 hours a year.

But even seasoned tour pilots have been caught in Hawai'i's rapidly changing weather conditions, with fatal results. The NTSB blamed pilot error for flying into bad weather as the cause of a 2000 tour helicopter crash on Maui that killed seven, a 1998 crash on Kaua'i's Mount Wai-'ale'ale that killed six, and two fatal air-tour crashes on Haleakala in 1992 that left 16 dead. One of the aircraft in those crashes was a Beech E18S plane.

Although final NTSB reports have not been issued, bad weather also is believed to have played a factor in more recent flightseeing fatalities.

The NTSB has completed its on-island investigation of Friday's helicopter wreck, and a preliminary report is expected within a few days. But a final probable-cause report may take longer.

There is still no probable cause listed in probes of the previous three fatal copter crashes in Hawai'i, dating back to mid-2003.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.