The circumstances were different, but Oahu’s two most recent fatal aircraft incidents both underscore a common concern, now more pressing than ever, about safety precautions that are in effect for Hawaii adventure-seekers.

Particularly painful was the fate of a fixed-wing plane destroyed in a fiery crash on Friday, just after takeoff for a sunset skydiving trip, killing all 11 aboard. The three deaths from the April helicopter accident on Oneawa Street in Kailua come to mind readily, but what happened Friday on the Dillingham Airfield was a surpassing horror.

The loss of life on the North Shore aboard the twin-engine plane, a Beechcraft King Air BE 65-A90, makes this the deadliest civilian aircraft accident in the U.S. since 2011, when a pilot and 10 spectators died at the Reno Air Show, according to the National Transportation Safety Board.

Jennifer Homendy, an NTSB board member, said in a media briefing on Monday that the investigation to learn the causes of this incident had just begun, with a preliminary report not expected for two weeks. Photos and videos of the aircraft (tail number N256TA) taken in the last two years are being sought and should be sent to the NTSB at witness@ntsb.gov.

She added that the current investigation will gather information on the pilot performance, the operations of the parachute center, the aircraft inspection and maintenance record, and the federal oversight of the operator and pilot.

However, even in the absence of hard facts on this case, Homendy was quick to point out that the NTSB, which advises the Federal Aviation Administration, has long advocated for hardening safety rules governing parachute jumping activities.

In September 2008, the NTSB issued “Special Investigation Report on the Safety of Parachute Jump Operations,” which analyzed 32 skydiving accidents that had occurred since 1980, including two in Hawaii. And since that report, Homendy said, there have been 80 accidents causing 19 more deaths.

According to the report, the board identified “recurring safety issues”:

>> Inadequate aircraft inspection and maintenance.

>> Pilot performance deficiencies in basic airmanship tasks, such as preflight inspections, weight and balance calculations, and emergency and recovery procedures.

>> Inadequate FAA oversight and direct surveillance of parachute operations.

Homendy acknowledged that there are “inherent risks” in parachute jumping that can be mitigated.

“But paying passengers should be able to count on an airworthy plane, an adequately trained pilot, a safe operator and adequate federal oversight of those operations,” she said.

In the 2008 report, the NTSB noted that parachute jumping is regulated by a different section of the law than other passenger operations — a “weaker” set of regulations. The differences, Homendy said, include rules governing training, aircraft inspection and maintenance and in federal oversight.

The NTSB is correct to push for stronger rules to direct skydiving businesses, and the FAA should be responsive to queries about why this has not happened.

Hawaii’s congressional delegation should be first in line asking questions; U.S. Rep. Ed Case, for one, has called for a discussion about FAA regulations.

There are particular reasons for concern about this episode, and this specific airplane, which was involved in a 2016 accident in California. Although that involved pilot error and the craft condition was not blamed, the NTSB rightly plans to look carefully at the repairs made.

Federal authorities must shed more light on what consumer-safety precautions are being taken here. Until they do, the shadow cast over the skydiving business is a dark one, indeed.