Hughes 369D accident near Zachary, Louisiana, December 9, 2004
On December 9, 2004 at about 9:15 pm local time, a Hughes 369D (helicopter), registered N7148Z, was substantially damaged in an accident near Zachary, Louisiana. It was an other work-use flight 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
The loss of engine power as a result of fatigue cracking of the compressor adaptor coupling initiated by fretting on the pilot diameter and subsequent disconnection of the compressor from the turbine assembly. A contributing factor was the low operating altitude of the helicopter, which made a successful autorotation by the pilot imposible.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 9, 2004 · about 9:15 pm local time
- Place
- Zachary, Louisiana · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Hughes 369D · all 369Ds on the register
- Registration
- N7148Z · no longer on the register · serial 570136D
- Damage
- Substantial damage
- Flight
- Other work-use flight · external-load helicopter rules (Part 133)
The NTSB's narrative final · quoted from the NTSB record
While performing aerial side-trimming of trees and bushes for a pipeline right-of -way using an external saw at an altitude of about 200 feet, the 14,000-hour pilot experienced a left yaw and what he perceived to be an engine failure. The pilot released the external load as he attempted an autorotation from an out-of-ground effect hover at 200 feet agl. Crushing damage to the airframe was consistent with a ground impact at a high rate of descent. A detailed examinations of the engine confirmed the reported loss of engine power. The engine examination revealed the Rolls-Royce manufactured compressor adapter coupling, which had been installed approximately 414 hours earlier, had disconnected the compressor assembly from the turbine assembly as a result of fatigue cracking initiated by fretting on the pilot diameter.
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: commercial pilot
- Ratings: single-engine land; rotorcraft: helicopter
- Flight time: 14,000 hours in all; 830 in this make and model
- Last flight review: March 1, 2004
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: serious injuries
The aircraft
- Airframe total time: 19,906.5 hours
- Last inspection: 100-hour inspection, December 1, 2004; 19.4 hours since
- Maximum gross weight: 3,550 lb
- Seats: 1
- Landing gear: fixed
- Engine: Allison 250-C20B (turboshaft); 0 hours total
The flight
- Departed from: Zachary LA at 9:25 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 220° at 7 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 75°F (24°C), dew point 50°F (10°C)
- Altimeter: 29.96 inHg
- Observation at 8:53 pm from BTR, 118 miles away
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.
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.