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NYC08LA318 · Hiller UH-12E

16 Sept 2008 · Naruna, VA, United States

Summit Helicopters Hiller UH-12E · Accident: flight control system malfunction/failure while maneuvering

From Naruna, VA to Naruna, VA

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Event

NTSB case
NYC08LA318
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
Unknown
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

Hiller UH-12E

Aircraft type
Hiller UH-12
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
N3324F
Onboard fatalities
Unknown
Route
From Naruna, VATo Naruna, VA
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 137: Agricultural
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
Defining eventThe 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
Flight control system malfunction/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

  • Aircraft › Aircraft propeller/rotor

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

NTSB narrative

While in straight and level flight, the pilot indicated that the helicopter began a "violent horizontal circular shake or wobble," and the main rotor rpm and began to decrease. The pilot entered an autorotation, turned the helicopter to the left to avoid trees, and touched down. During the forced landing, the tail rotor contacted the ground, and after the engine had been shut down, one of the main rotor blades contacted the tailboom. Post accident examination revealed that a main rotor blade drag strut had failed at the inboard threaded portion of the strut. Further examination revealed that a vibro-peen marked serial number was visible on the failed drag strut and that the drag strut had failed due to fatigue cracking that emanated from the root portion of the threads. The helicopter's maintenance records listed the failed drag strut as being a part number that should have had a life limit of 2,500 hours, but failed at 2,236 hours. Contrary to the helicopter manufacturer’s drawings, there was no part number on the failed drag strut, which put into doubt the actual hours of operation on the part.

Probable cause

The fatigue failure of a main rotor blade drag strut.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record NYC08LA318
Event ID
20081007X16231
Case number
NYC08LA318
Dataset
full-current
Source SHA-256
5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
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: 4daf2f4d48900c4921ae95da3ebe855214b787960160aa8a560da877260cab82; retrieved 2026-09-15T10:25:21.410Z.