The remains of six people have been found after a helicopter heading to one of the most rugged and remote coastlines in Hawaii crashed at the top of a mountain on the island of Kauai, authorities said.
Officials said on Friday that there are no indications of survivors and that a search for the last person yet to be recovered would resume in the morning, depending on the weather.
Those who were recovered have not been identified and their families are being notified, authorities said.
A search began for the helicopter carrying a pilot and six passengers from two families after it was reported overdue Thursday evening from a tour of Kauai's Na Pali Coast. Two passengers are believed to be minors, the Coast Guard said.
Steep terrain, low visibility, choppy seas and rain had complicated the search, the agency said.
The helicopter company, identified as Safari Helicopters, contacted the Coast Guard about 6 pm on Thursday to say the aircraft was about 30 minutes overdue, authorities said.
A person who answered the phone at a number listed for Safari Helicopters declined to comment and hung up.
According to a preliminary report, the pilot said the tour was leaving the Waimea Canyon area, known as the 'Grand Canyon of the Pacific', about 4:40 pm, which was the last contact with the helicopter, Kauai police said.
The Eurocopter AS350 has an emergency electronic locator transmitter, but no signals were received. The locator devices are designed to activate when an aircraft crashes, Federal Aviation Administration spokesman Ian Gregor said in an email.
The FAA requires the locators to be able to withstand impact. However, it is possible for the device to stop working in an extreme crash, Gregor said.
He said the agency is looking at the company's safety record but likely won't have a full report until Monday. It's investigating along with the National Transportation Safety Board.
US Rep. Ed Case of Hawaii cited fatal accidents over the years, blaming the FAA for not taking NTSB safety improvement efforts seriously and the industry for not regulating itself. He said “innocent lives are paying the price."
The FAA said it conducts random and regular surveillance on all Hawaii air tour operators and ensures companies address any issues. Gregor said the agency does not have concerns about the industry statewide.
The NTSB aviation accident database lists nine crashes of Hawaii helicopter sightseeing flights in the last 10 years, including three with fatalities.
After a Hawaii skydiving plane crashed and killed 11 people in June, the NTSB called on the FAA to tighten its regulations governing parachute operations. The FAA said at the time that it had made changes to address NTSB recommendations.
The chopper that crashed this week along a route used by all tour helicopters was found in a mountainous region inland from the Na Pali Coast, which is one of the most dramatic and sought-after destinations in Hawaii and was featured in the film 'Jurassic Park'.
Towering mountains with deep ravines and huge waterfalls make up the interior of the uninhabited state park. Red rock cliffs with thick jungle canopies rise from the Pacific Ocean to over 1,219 metres high.
Ladd Sanger, a Texas-based aviation attorney and helicopter pilot who has handled several crash cases involving similar helicopters in Hawaii, said tour operators on Kauai face unique challenges because of weather and topography.
Kauai "has microclimates, so the weather at the airport is going to be different than up at the crash location," Sanger said. "Those microclimates can come on very quickly and dissipate quickly too, so the weather reporting is difficult."
Hawaii Department of Land and Natural Resources spokesman Dan Dennison, who has spent years visiting and photographing the area, said winter brings more rain and turbulent seas.
"You can have very low ceilings. You can have fog and cloud banks that move in very quickly. You can have heavy rain and strong winds that make flying difficult if not impossible at times," he said.
The shoreline has beaches that could potentially serve as emergency landing zones, but they are "few and far between", Dennison said.
And even the beaches that are there would be a tight spot to land a helicopter.
"Kauai is incredibly unforgiving terrain," Sanger said. "If you lose the engine there's just really no place to land on the tour route that they were flying."