LAX86MA309 · Aerospatiale AS-355F-1
Mobil Oil Aerospatiale AS-355F-1 · Accident: airframe, component or system failure on approach
Event
- NTSB case
- LAX86MA309
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Aerospatiale AS-355F-1
- Aircraft type
- Aerospatiale AS-355
- Category
- Helicopter
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N57967
- Operator
- Mobil Oil
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Approach · VFR pattern final
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Airframe, component or system failure
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Reason for occurrence undetermined
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
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.
Verbatim NTSB analysis from the NTSB dataset
Sources
NTSB record LAX86MA309
- Event ID
- 20001213X34236
- Case number
- LAX86MA309
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 2f1fe195bd36649aec8631831dda20e5fd22f14e98df0703513fed082cc4e814; retrieved 2026-09-23T14:16:40.416Z.