A fatal crash involving a sightseeing flight near Ketchikan, Alaska, last week renewed concerns about aviation safety in a state that accounts for more deaths in small commercial aircraft crashes than anywhere else in the nation.

Six people — a pilot and five passengers — died Thursday when a de Havilland Beaver float plane went down eight miles northeast of the Southeast Alaska city of 8,000 that is a cruise ship hot spot. The passengers had been aboard the Holland America Line cruise ship the Nieuw Amsterdam, which only recently resumed operations in the state after a pause related to the COVID-19 pandemic.

The National Transportation Safety Board has started an investigation. So far this year, 13 people have died in three fatal small commercial crashes, including the latest. The past year and a half has been particularly deadly for small commercial aviation despite COVID-19 limiting air travel. Last year, 15 people died in crashes involving such flights, the highest total since 2013, and this year has nearly equaled that figure with more than four months still left in the year.

The crashes are raising concerns.

“It’s very distressing to see yet another sightseeing accident occur,” said Robert Sumwalt, recently retired chairman of the NTSB, which released a final report this spring on a 2019 sightseeing plane crash in the same area. “I feel that this accident just shows there’s still a lot of work to be done.”

A KUCB and ProPublica investigation in June found that Alaska is home to a growing share of the country’s crashes involving small commercial aircraft. Over the past two decades, the number of deaths in crashes involving these operators has plummeted nationwide, while in Alaska deaths have held relatively steady. As a result, Alaska’s share of fatalities in such crashes has increased from 26% in the early 2000s to 42% since 2016. Our analysis included crashes involving at least one plane or helicopter flying under the Federal Aviation Administration’s typical rules for commuter, air taxi or charter service. (The flight safety record of large air carriers is strong both in Alaska and nationally.)

Experts, including Sumwalt, told the news organizations that the Federal Aviation Administration could be doing more to improve the safety of air travel in Alaska. The FAA said it has made the issue a top priority.

This is not the first crash near Ketchikan, where flightseeing tours of the Misty Fjords National Monument are popular for their glorious views of the area’s glacial valleys and steep cliffs.

In late July 2007, sisters Jeanne Eddy and Marianne McManus died alongside their husbands when their sightseeing plane crashed into mountains near Ketchikan while visiting Alaska on a cruise. “This crash is a little eerier since it seems to be in roughly the same spot,” said Bill Heuer, their brother.

Heuer and his family don’t live in Alaska, but since their family disaster, they have become aware of other commercial crashes in the state. “It brings back lots of unhappy thoughts,” he said.

In May 2019, a midair collision near Ketchikan killed six people. In June 2015, a plane returning from the Misty Fjords collided with a mountain, killing the pilot and eight passengers. In July 2007, a plane was destroyed, killing all five on board, when it crashed in mountainous tree-covered terrain about 40 miles northeast of Ketchikan. Passengers from cruise ships were aboard all three flights.

Thursday’s crash also isn’t the first involving its operator, Southeast Aviation LLC, which has a fleet of six-passenger float planes. Last month, a Southeast Aviation floatplane crashed during takeoff near the Prince of Wales Island community of Coffman Cove. The pilot was the only person on board and was not injured. The pilot in last month’s crash, Rolf Lanzendorfer, was also the pilot in Thursday’s crash, according to the NTSB. Lanzendorfer had worked as a pilot for Southeast Aviation since May 2015.

In 2012, a Southeast Aviation charter flight crashed into water on its way back to Ketchikan from a mine site on Prince of Wales Island. Shortly after departure, the weather deteriorated; the pilot later reported that heavy snow had reduced visibility to nearly zero. The pilot and passenger were both injured, but survived.

Southeast Aviation issued a statement Thursday that said, “All of us share in the anguish of this tragic incident, and our prayers go out to all affected.” The company did not return a call or email seeking further comment. It is one of 14 commercial operators that have worked together to establish safe operating procedures for flying in Ketchikan and the Misty Fjords National Monument Wilderness area.

Over the years, advances in technology have been developed to help prevent aviation accidents. Computer systems called Automatic Dependent Surveillance-Broadcast, or ADS-B, have been associated with a decrease in accidents and are required in nearly all of the lower 48 states. However, the rule only applies to controlled airspace, which the Federal Aviation Administration agency defines in a way that excludes most of Alaska, including Ketchikan and the Misty Fjords.

The Southeast Aviation plane was equipped with ADS-B, but it is too soon to know if the technology was working properly or whether it could have helped to prevent the accident.

Hours after the flight disappeared, the U.S. Coast Guard located the plane’s wreckage in a steep mountainous area near Misty Fjords. On Saturday, the Alaska State Troopers and Ketchikan Volunteer Rescue Squad recovered the bodies of the crash victims.

In addition to the pilot, state troopers have identified the five Holland America cruise ship passengers as: Mark Henderson and Jacquelyn Komplin of Napa, California; Andrea McArthur and Rachel McArthur of Woodstock, Georgia; and Janet Kroll of Mount Prospect, Illinois.

The NTSB sent a team to Ketchikan to investigate the accident. It can take years for the NTSB to finish an investigation and determine the probable cause of an accident.

On Saturday — two days after this accident — the Coast Guard rescued two people from another plane crash on a lake in the Misty Fjords National Monument. The private plane crashed during takeoff, and no injuries were reported.