Aerospatiale AS-355F-1 accident near Morgan City, Louisiana, July 18, 1986
On July 18, 1986 at about 12:55 pm local time, a Aerospatiale AS-355F-1 (helicopter), registered N57967, was destroyed in an accident near Morgan City, Louisiana (Mobil Oil Heliport airport). It was an instructional flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 18, 1986 · about 12:55 pm local time
- Place
- Morgan City, Louisiana · Mobil Oil Heliport · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Aerospatiale AS-355F-1 · all AS-355F-1s on the register
- Registration
- N57967 · no longer on the register · serial 5169
- Damage
- Destroyed
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE PLT FLEW TO A NEARBY ARPT TO PRACTICE TAKEOFFS & LNDGS. HE RPRTD THAT AFTER 3 LNDGS 'OUT OF A HOVER,' HE RETURNED TO THE DEPARTURE HELIPORT & LNDD AGAIN FROM A HOVER. DRG TOUCHDOWN, THE HELICOPTER BGN TO ROCK FM SIDE TO SIDE & ENTEREDGROUND RESONANCE. THE PLT RPRTD HE LOWERED THE COLLECTIVE PITCH TO THE BOTTOM STOP, BUT STATED THE SIDEWARD BOUNCING FM SKID TO SKID WORSENED. HE REACHED FOR THE OVERHEAD THROTTLES, BUT WAS BEING FLAILED ABOUT THE COCKPIT & COULD NOT HOLD ONTO THEM. SUBSEQUENTLY, THE HELICOPTER WAS EXTENSIVELY DAMAGED. WITNESSES VERIFIED THE SIDE TO SIDE BOUNCING & RPRTD HEARING A LOUD METALLIC SOUND BEFORE THE HELICOPTER TOUCHED DOWN. A POST-CRASH EXAM REVEALED THE L FRONT, L REAR & RGT REAR SUPPORT TUBES (GEARBOX BARS) WERE BUCKLED IN A 'D' SHAPE & FRACTURED AT MIDSPAN. METALLURGICAL EXAM OF THE FRACTUREAREAS DISCLOSED EVIDENCE OF HIGH STRESS, LOW AMPLITUDE FATIGUE. NO HISTORY OF HARD LNDGS OR MAINTAINANCE/MANUFACTURING DISCREPANCIES WERE FND CONCERNING THE GEARBOX BARS; L FRONT BAR HAD 1522 HRS OF SVC, REAR BARS HAD 3396 HRS OF SVC.
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, flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: helicopter; instructor: instrument airplane; instructor: instrument helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 16,500 hours in all; 15 in this make and model; 320 in the last 90 days; 16,400 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 3,397 hours
- Last inspection: continuous airworthiness programme, July 11, 1986; 20 hours since
- Maximum gross weight: 4,600 lb
- Seats: 5
- Landing gear: fixed
- Engine: Allison 250-C20F (turboshaft); 0 hours total
- Operator: Mobil Oil CORP.
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 81°F (27°C), dew point 0°F (-18°C)
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.