Strong wind gusts and moderate to heavy rainfall occurred when a student pilot and his flight instructor appeared to lose control of a Robinson R44 helicopter that plunged into waters off of Molokai in October 2017, killing them both, according to a report released by the National Transportation Safety Board.
The federal agency released a report this week on the weather conditions at the time of the crash, which occurred northwest of the Molokai Airport on the night of Oct. 16. The report also includes detailed information on the portion of the wreckage recovered earlier this year.
Jeremy Dossetter, 27, who had a commercial pilot certificate, and instructor Oliver Kirsch, 25, of Mauna Loa Helicopters were never found and presumed dead after the Coast Guard scoured more than 9,300 square miles for three days searching for them.
NTSB spokesman Keith Holloway said Thursday in an interview with the Honolulu Star-Advertiser that the probable cause and findings of the crash had yet to be determined.
“The investigation is still ongoing,” said Holloway, adding the cause could be released by the end of the year.
The crash occurred at about 7:18 p.m.
Dossetter and Kirsch were approaching Molokai Airport on an an instructional flight using an instrument approach. After they successfully completed the practice approach, air traffic controllers gave them clearance to return to Daniel K. Inouye International Airport.
The NTSB report described the events when the men appeared to lose control of the aircraft before they disappeared from radar.
Radar data showed the helicopter traveling north-northeast while climbing to 3,500 feet from 1,700 feet about a mile off of Molokai Airport before it turned left and continued to climb to 4,000 feet.
The aircraft then turned right and then left, dipping to 3,700 feet. The report said it continued southeast as it slightly ascended before turning west. Soon after, the helicopter dropped to 2,700 feet and disappeared from radar about 6 miles northwest of the airport.
Doppler radar captured images that depicted moderate to heavy rainfall in the vicinity of the crash site. “Rain showers and convective clouds produce outflow boundaries and gust fronts throughout their life cycle. An outflow boundary or gust front can create an environment favorable for unexpected changes in wind direction and speed,” investigators said in the report.
Wind conditions at the time were wind speeds at 13 knots and gusts at 24 knots.
The Coast Guard responded to a report of a missing helicopter and spotted debris and a red chemlight floating in waters off of Molokai. An uninflated life jacket was also found along the northwest coast of the island.
The report said one of the two men had checked the weather conditions via ForeFlight at about 6 p.m. that day. The National Weather Service forecast scattered rain showers and tradewinds that would bring strong gusty northeast winds.
In January a private company recovered a portion of the wreckage 2 miles off of Molokai which showed “no evidence of any mechanical damage or heat distress” in the engine.
The helicopter was registered to Stasys Aviation Leasing LLC and operated by Hawaii Pacific Aviation doing business as Mauna Loa Helicopters.
NTSB Safety Board Aviation Accident Factual Report by Honolulu Star-Advertiser on Scribd
