The National Transportation Safety Board says the defining event in a crash that killed five people aboard a skydiving flight on Kauai last year was “loss of control in flight.”

The information was released earlier this month in a factual report for the May 23, 2016, crash at Port Allen Airport in Hanapepe.

The pilot, 30-year-old Damien Horan, of Waimea, was killed along with brothers Marshall and Phillip Cabe of Lawton, Okla., and Skydive Hawaii instructors Enzo Amitrano and Wayne Rose.

The skydiving excursion was a college graduation present for the brothers from their father, Michael Cabe, the family’s attorney Rick Fried said last year.

Cabe, who was a Kauai contractor at the time, dropped off his sons at the airport and watched the plane take off, Fried said. Cabe heard the aircraft’s engine sputter and die and watched the plane crash.

He rushed to the crash scene and pulled his sons out of the burning wreckage and began performing CPR to no avail. Last year, the brothers’ parents sued David Timko, owner of D&J Air Adventures Inc., the registered owner of the crashed Cessna. The civil case is still pending.

The factual NTSB report on the crash did not cite a cause, but did say an airframe and engine examination “did not reveal evidence of any preexisting mechanical malfunction.”

A test for alcohol and other drugs in the pilot’s system was negative, the report said.

A security video of the crash released by the NTSB showed a grainy image of the plane descending nose first while rolling before a fiery explosion on the ground.

The airplane, a Cessna 182, crashed at the edge of a dirt road outside the airport perimeter fence, the report said.

The plane was built in 1965 and had the passenger seats removed for parachuting use in 1972. The engine was installed in November 2013, but appears from the report to have been used.

A calculation of the gross weight of the aircraft was about 2,810 pounds — 10 pounds over the maximum allowable weight, the report said.

The report said the airplane was refueled at a nearby gas station the day of the flight and had a certificate allowing the use of automotive gasoline, but not ethanol-containing fuel. The report noted a fuel system using ethanol-mixed gasoline has a higher probability of developing conditions that can disrupt engine operation and that Hawaii does not require a sign for gas pumps containing less than 1 percent ethanol. No tests were done to determine whether ethanol was in the fuel.

According to the report, the pilot had 321 total flight hours and received a medical certificate with no limitations in February 2016. He reported completing 53.2 flight hours in the six months prior to his medical test, and the most recent entry in his pilot’s logbook was a 1.1-hour flight on March 5, 2016.

The report said the pilot was using a lap belt, but none of the other passengers was seen using restraints in videos before takeoff. Three other people, who previously jumped from the same plane, told investigators that they did not see or use seat belts during their flights.

Video from a GoPro camera onboard the plane showed it crashed about 33 seconds from takeoff, and a sound study of the video showed the engine speed dropped from 2,650 rpm to about 1,215 rpm in about 10 seconds. A stall warning horn was not heard on the recording, the report said.

The report ends with a note that the Federal Aviation Administration’s Airplane Flying Handbook says if an engine failure occurs on takeoff, “the pilot should establish a proper glide attitude and select a landing area straight ahead with only small changes in direction.”

NTSB Aviation Accident Factual Report by Honolulu Star-Advertiser on Scribd