Mcdonnell Douglas 369D accident near Waialua, Hawaii, May 13, 1988
On May 13, 1988 at about 8:15 pm local time, a Mcdonnell Douglas 369D (helicopter), registered N4943T, was destroyed in an accident near Waialua, Hawaii (Field). It was a flight of an unrecorded kind under external-load helicopter rules (Part 133). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
FAILURE TO FOLLOW PROCEDURES ESTABLISHED BY THE MANUFACTURE FOR UNCOMMANDED TRIM INPUTS AND HIS DECISION TO MAKE A HOVER APPROACH TO LANDING.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 13, 1988 · about 8:15 pm local time
- Place
- Waialua, Hawaii · Field · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Mcdonnell Douglas 369D
- Registration
- N4943T · no longer on the register · serial 400694D
- Damage
- Destroyed
- Flight
- Flight of an unrecorded kind · external-load helicopter rules (Part 133)
The NTSB's narrative final · quoted from the NTSB record
THE HELICOPTER WAS RETURNING TO ITS LONG LINE PICKUP POINT FOR ANOTHER LOAD WHEN IT ENTERED AN UNCOMMANDED LEFT ROLL. THE PILOT REGAINED CONTROL OF THE HELICOPTER, RELEASED THE LONG LINE CABLE AND ENTERED A SHALLOW, SLOW APPROACH TO A HOVER IN A VACANT AREA. AS THE SKIDS NEARED THE GROUND THE HELICOPTER ROLLED LEFT TO AN ANGLE OF 45 DEGREES, BEGAN TO CLIMB, THEN CRASHED INTO AN IRRIGATION DITCH. THE EXAMINATION REVEALED METAL PARTICLES CONTAMINATING THE TRIM ACTUATOR SWITCH. ACCORDING TO THE MANUFACTURER, THE HELICOPTER IS CONTROLLABLE WITH A MALFUNCTIONING TRIM SYSTEM; HOWEVER, THE CIRCUIT BRAKERS SHOULD BE PULLED. THE PILOT STATED HE RESET THE CIRCUIT BREAKERS.
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
Pilot
- Certificate: airline transport pilot, commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 8,600 hours in all; 5,000 in this make and model; 250 in the last 90 days; 80 in the last 30 days; 8,600 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 3,102 hours
- Last inspection: 100-hour inspection, April 10, 1988; 82 hours since
- Maximum gross weight: 3,000 lb
- Seats: 4
- Landing gear: fixed
- Engine: Allison 250-C20B (turboshaft); 0 hours total
- Operator: Cherry Helicopters, INC.
The flight
- Departed from: Waialua HI at 8:10 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 020° at 3 knots, gusting 7
- Visibility: 7 statute miles
- Sky: broken clouds at 2,000 ft; scat at 1,500 ft
- Temperature: 75°F (24°C), dew point 66°F (19°C)
- Altimeter: 30.00 inHg
- Observation at 8:00 pm from HHI
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Other NTSB records under N4943T the same tail number, which may have belonged to a different aircraft at the time
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.