# NTSB LAX84LA478: Agusta A109, N57BL, Clifton, AZ, September 12, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 12, 1984, 16:20 local (23:20 UTC)
- Place: Clifton, AZ
- Coordinates: 33.270313, -109.269126 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=33.2703&lon=-109.2691&mi=10
- Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 24398
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX84LA478
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/24398/pdf
- Page: https://openairdocs.org/ntsb/LAX84LA478

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of control - on ground/water, standing - engine(s) operating
  - fuselage - vibration
  - reason for occurrence undetermined (cause)
- Main gear collapsed, other

## Analysis

THE PLT REPORTED THAT HE LANDED FIRMLY ON THE GROUND AT THE MAIN RAMP & WENT INTO THE 2 MIN COOL DOWN MODE FOR ENG SHUTDOWN. HE STATED THAT IMMEDIATELY AFTER THE POWER LEVERS WERE RETARDED TO IDLE, HE FELT A SLIGHT LATERAL MOVEMENT OF THE CONTROLS WHICH WAS FOLLOWED BY AN ACCELERATED LATERAL MOVEMENT OF THE HELICOPTER. HE STATED THAT THE HELICOPTER THEN WENT INTO A VIOLENT LATERAL & FORWARD VIBRATION. HE SHUT OFF THE ENG & APPLIED THE ROTOR BRAKE. HOWEVER, BEFORE THE VIBRATION STOPPED, THE TAILROTOR ASSEMBLY HIT THE GROUND & THE MAIN GEAR COLLAPSED. NO PRE-ACCIDENT PART FAILURE OR MALFUNCTION WAS FOUND THAT WOULD HAVE RESULTED IN THE VIBRATION OR GROUND RESONANCE.

## Aircraft

- Registration: N57BL (not matched to a registry record)
- Reported make and model: AGUSTA A109
- Category: Helicopter
- Serial number: 7199
- Airframe hours: 583
- Engines: ALLISON 250-C20B 420 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Popeye'S Famous Fried Chicken
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, September 11, 1984, 10 hours before
- Departed: SVC, SILVER CITY, NM
- Destination: SDL, SCOTTSDALE, AZ
- Airport: Greenlee Co., runway 25, 4,960 × 75 ft, concrete

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 40; airline transport; airplane ratings: single-engine land, multi-engine land, single-engine sea; instrument ratings: helicopter, airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 7,700 total, 110 in this make and model, 7,500 as pilot in command, 175 in the last 90 days, 50 in the last 30 days, 7 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 240° at 5 knots
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 88 °F, dew point 59 °F

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19840912050999A](https://openairdocs.org/incident/19840912050999A), Sep 12, 1984: Agusta A109A, Clifton, AZ, Substantial damage. Reported shut down vibration, tail rotor struck ground. No defects found, source of vibration undetermined.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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