Robinson Helicopter R44 accident near Kekaha, Hawaii, July 11, 2024
On July 11, 2024 at about 11:05 pm local time, a 2009 Robinson Helicopter R44, registered N144KW, was substantially damaged in an accident during enroute near Kekaha, Hawaii. It was an aerial observation flight under general aviation rules (Part 91). 3 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
An encounter with turbulence due to downdraft winds that resulted in mast bumping and an in-flight breakup.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 11, 2024 · about 11:05 pm local time
- Place
- Kekaha, Hawaii · map
- Type
- Accident
- Injuries
- 3 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson Helicopter R44, built 2009 · all R44s on the register
- Registration
- N144KW · registry record · serial 12805
- Damage
- Substantial damage
- Flight
- Aerial observation flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The helicopter was on a local air tour when the accident occurred. Witnesses reported strong, gusting wind and that a “huge” and sudden gust of wind blew over them, which was followed by a very loud “bang” noise. As their attention was drawn to the source of the loud noise, they saw the helicopter wreckage freefalling into the ocean in two sections: a main fuselage section and the tail boom section. Examination of the wreckage revealed no evidence of any preexisting anomalies that would have precluded normal operation of the helicopter. There was evidence that a mast bumping event had occurred and that the main rotor blades had contacted the airframe, which resulted in an in-flight breakup. There was no recorded information available that could be used to determine the helicopter's airspeed, altitude, or the pilot's control inputs. A weather study indicated that conditions were conducive to the development of strong downdraft winds. It is likely that the helicopter encountered turbulence due to downdrafts, which resulted in mast bumping and a subsequent in-flight breakup. Robinson Safety Notice SN-32 discusses flight in high winds and turbulence and explains how improper application of control inputs in response to turbulence can increase the likelihood of a mast bumping accident. It recommends that pilots reduce airspeed below normal cruise speed to 60 to 70 knots for flight in significant turbulence. It suggests techniques to avoid overcontrol of the helicopter and says to avoid flying on the downwind side of hills and ridges.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Mast bumping during enroute defining event
- Loss of control in flight during enroute
- Aircraft structural failure during enroute
- Turbulence encounter during enroute
- Part(s) separation from AC during enroute
The NTSB's findings
- Aircraft › Aircraft propeller/rotor › Main rotor system › Main rotor mast/swashplate › Related operating info
- Environmental issues › Conditions/weather/phenomena › Turbulence › Terrain induced turbulence › Effect on operation
- Personnel issues › Task performance › Use of equip/info › Use of policy/procedure › Pilot
Pilot
- Certificate: airline transport pilot, flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: helicopter; instructor: instrument airplane; instructor: instrument helicopter; instrument: airplane; instrument: helicopter; rotorcraft: glider; rotorcraft: helicopter
- Flight time: 25,000 hours in all; 6,000 in this make and model; 200 in the last 90 days; 70 in the last 30 days; 25,000 as pilot in command; 2,000 on instruments
- Last flight review: June 27, 2024
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: fatal
Passenger
- Seat: rgt
- Injury: fatal
Passenger
- Seat: left
- Injury: fatal
The aircraft
- Airframe total time: 1,190.1 hours
- Last inspection: 100-hour inspection, July 8, 2024
- Maximum gross weight: 2,500 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-540-AE1A5 (piston); 1,203 hours total
- Operator: Ali’I Air Tours
The flight
- Departed from: LIH Lihue HI at 10:31 pm
Weather at the time
- Light: daylight
- Wind: from 020° at 17 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 4,800 ft
- Temperature: 82°F (28°C), dew point 70°F (21°C)
- Altimeter: 30.04 inHg
- Observation at 12:53 pm from HLI, 21 miles away
Weather report (METAR): PHLI 112253Z 02017KT 10SM FEW048 SCT060 28/21 A3004 RMK AO2 PK WND 06029/2155 RAE09 SLP170 P0001 T02780211
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
18 documents, released by the NTSB on June 4, 2025. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Meteorology Factual Report | PDF, 29 pages · our copy | View Download |
| 2 | Meteorology Attachment 1 -faa Makaha Ridge N Weather Camera Imagery | video · our copy | View Download |
| 3 | Meteorology Attachment 2 - Princeviile W Weather Camera | video · our copy | View Download |
| 4 | Meteorology Attachment 3 - GOES-18 Infrared Satellite Imagery | GIF file · our copy | Download |
| 5 | Meteorology Attachment 4 - GOES-18 Geocolor Satellite Imagery | GIF file · our copy | Download |
| 6 | Meteorology Attachment 5 - GOES-18 Water Vapor Imagery | GIF file · our copy | Download |
| 7 | Meteorology Attachment 6 - Nws Phki WSR-88D radar Animation | AVI file · our copy | Download |
| 8 | Personal Electronic Device - Specialist's Factual Report | PDF, 5 pages · our copy | View Download |
| 9 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 9 pages · our copy | View Download |
| 10 | Witness Statements | PDF, 6 pages · our copy | View Download |
| 11 | ADS-B | data file · our copy | Download |
| 12 | Wreckage Examination | PDF, 12 pages · our copy | View Download |
| 13 | Pilot's Safety Course | PDF, 8 pages · our copy | View Download |
| 14 | Robinson Safety Notice SN-32 | PDF, 1 page · our copy | View Download |
| 15 | No Autopsy - No Toxicology | PDF, 1 page · our copy | View Download |
| 16 | Certification of Party Representatives | PDF, 16 pages · our copy | View Download |
| 17 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page · our copy | View Download |
| 18 | Investigative Photographs | PDF, 2 pages · our copy | View Download |
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.