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ANC93FA061 · Bell 214B1

8 May 1993 · THORNE BAY, AK, United States

Bell 214B1 · Accident: total loss of engine power (mechanical failure) while maneuvering

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Event

NTSB case
ANC93FA061
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

Bell 214B1

Aircraft type
Bell 214
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
N314CR
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 133: Rotorcraft Ext. Load
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
Maneuvering · hover
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
Total loss of engine power (mechanical failure)
DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
Substantial

Cause areas

  • Compressor assembly › Foreign object damage
  • Compressor assembly › Other
  • Other maintenance personnel › Maintenance, improper

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

THE HELICOPTER WAS BEING USED TO MOVE LOGS IN A LONG-LINE LIFT OPERATION. THE PILOT REPORTED THAT AS HE INCREASED COLLECTIVE TO LIFT A LOG, HE HEARD A LOUD NOISE, WHICH WAS FOLLOWED BY A LOSS OF POWER. AN AUTOROTATION WAS MADE TO A LANDING ON ROUGH, DOWNHILL TERRAIN, DOWNSLOPE FROM WHERE THE LOG WAS BEING LIFTED. A TEARDOWN OF THE ENGINE REVEALED EVIDENCE OF FOREIGN OBJECT DAMAGE AT THE 6TH AND 7TH STAGES OF THE N1 (GAS PRODUCER) COMPRESSOR. SELF-LOCKING NUTS (PN STD3064-4) WERE MISSING FROM 2 COMPRESSOR CASE BOLTS (PN MS9566-36), WHICH WERE LOCATED OVER A BLEED PORT, LEADING TO THE 6TH STAGE OF THE GAS PRODUCER. METALLURGICAL EXAM REVEALED NUT FRAGMENTS OF A CHEMICAL COMPOSITION, CONSISTENT WITH THE MATERIAL SPECIFIED IN STD3064-4 NUTS. THE ENGINE HAD BEEN IN OPERATION ABOUT 283 HOURS, AFTER BEING REASSEMBLED WITH A NEW COMPRESSOR SECTION.

Probable cause

FOREIGN OBJECT DAMAGE TO THE COMPRESSOR ASSEMBLY, PROBABLY DUE TO LOOSE NUTS FROM THE COMPRESSOR CASE AFTER IMPROPER MAINTENANCE (INSTALLATION) BY MAINTENANCE PERSONNEL.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record ANC93FA061
Event ID
20001211X12258
Case number
ANC93FA061
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: 4aec7b91cab3434292e1a2f9d0ed410d75983f899372bbbdafb8a212a203daca; retrieved 2026-09-21T22:57:48.675Z.