The National Transportation Safety Board released a preliminary report last week on the North Slope helicopter crash that killed a pilot and a passenger in June. Investigators still don't know what caused the crash. But the report highlights flat light conditions and relatively low cloud ceiling near the accident, as well as that the pilot was new to the area.
Alaska NTSB Chief Clint Johnson said that investigators have not eliminated pilot error, mechanical issue or weather conditions as potential factors leading to the crash.
“We're just getting started on this investigation,” Johnson said. “We're going to be looking at three main areas – we say it all the time, but it's man, machine, environment.”
The Robinson R66 helicopter operated by Wasilla-based Pollux Aviation left Deadhorse at around 10:40 a.m. on June 4 and crashed about 15 minutes later, according to the report. The purpose of the flight was to scout conditions for bird research. Shiloh Schulte, a shorebird scientist from New England, and pilot Jonathan Guibas died in the crash.
The North Slope Borough Search and Rescue crew located the wreckage 25 miles west of Deadhorse, “in an area of flat, snow-covered, featureless terrain,” according to the report. NTSB investigators recovered the wreckage several days later when the weather cleared.
The report points out that Guibas was new to Alaska, and the accident was his first flight on the North Slope with a passenger, though Johnson said it’s unclear if that played any role in the incident.
“It's not being emphasized but this was a data point that we thought was important to highlight,” he said.
Weather conditions near the accident site were overcast at 500 feet with visibility of 10 miles, according to the report.
Johnson said the pilot received a special visual flight rules clearance before the departure because of the relatively low ceiling. When the helicopter was about 15 miles west of Deadhorse airport, the pilot informed the air traffic facility that he was clear of the airport environment, the report said. The facility did not receive further radio contact from the helicopter, the report said.
While weather data is available at the Deadhorse airport, Johnson said the North Slope area lacks certified weather stations, and investigators have to rely on sparse reports from other pilots.
“The North Slope obviously has some challenges and some risks that are very unique, one of those being obviously flat light which makes it really tough to discern topographical features on the snow-covered surface there,” Johnson said. “But again, we don't know if that played a part in it.”
NTSB assigned a meteorologist to the case to get more information on the conditions the pilot encountered just before the accident, Johnson said.
Investigators relocated the wreckage to the Anchorage area for further examination within the next week, Johnson said. The final report is usually released about a year after the incident, he said.
