# NTSB MIA90LA134: Ayres S2R-600, N40145, Vero Beach, FL, May 26, 1990

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: May 26, 1990, 09:30 local (13:30 UTC)
- Place: Vero Beach, FL
- Coordinates: 27.639982, -80.389236 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=27.6400&lon=-80.3892&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report February 12, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 32666
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA90LA134
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/32666/pdf
- Page: https://openairdocs.org/ntsb/MIA90LA134

## Probable cause

THE OPERATION OF THE AIRPLANE WITH AN UNAIRWORTHY PROPELLER BY THE OPERATOR.

## Sequence of events

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

- Airframe/component/system failure/malfunction, maneuvering - aerial application
  - propeller system/accessories,pitch change mech - fatigue (cause)
  - maintenance,overhaul - disregarded, company/operator management (cause)
  - propeller system/accessories,pitch change mech - failure,partial
  - operation with known deficiencies in equipment - continued, company/operator management (cause)
- Forced landing, descent - emergency
- In flight collision with object, descent - emergency
  - object - tree(s)
  - unsuitable terrain or takeoff/landing/taxi area - encountered, pilot in command

## Analysis

THE PLT STATED THAT WHILE MANEUVERING, HE FELT A SEVERE VIBRATION. HE DUMPED THE CHEMICAL & DURING THE FORCED LANDING, COLLIDED WITH TREES BEFORE COMING TO REST. EXAM OF THE ACFT REVEALED THAT THE NO. 2 PROP BLADE COUNTERWEIGHT BEARING SHAFT FAILED DUE TO FATIGUE. ACCORDING TO THE METALLURGIST, THE FATIGUE WAS DUE TO BENDING STRESS WHICH WAS CAUSED BY EXCESSIVE CLEARANCE BETWEEN THE SHAFT & THE BUSHED HOLE IT WAS POSITIONED IN. THIS ALLOWED CENTRIFUGAL FORCE TO POSITION THE BLADE TO HIGH PITCH, RESULTING IN UNEQUAL THRUST. THE PROP WAS OVERHAULED IN 1987 BUT THE TOTAL TIME SINCE THAT TIME COULD NOT BE DETERMINED. THE PROP WAS REPAIRED ABOUT 10 WEEKS PRIOR TO THE ACCIDENT BUT HAD ONLY ACCUMULATED 3.4 HRS SINCE THE REPAIR. ACCORDING TO THE PROP OVERHAUL FACILITY GENERAL MGR, THE PROP WAS RETURNED TO THE OPERATOR AFTER THE ACCIDENT BUT THE APPROVED FOR SERVICE LINE ON THE WORK ORDER WAS NOT SIGNED. ACCORDING TO THE CHIEF INSPECTOR OF THE REPAIR FACILITY, FURTHER INSP WAS NECESSARY TO DETERMINE IF THE PROP WAS AIRWORTHY.

## Aircraft

- Registration: [N40145](https://openairdocs.org/deregistered/N40145-1996-03-22), registration cancelled 1996-03-22, S/N 2558R (OpenAirDocs)
- Reported make and model: Ayres S2R-600
- Registry model: [Ayres S2R-600](https://openairdocs.org/model/ayres-s2r-600) (registry code 0970102) (OpenAirDocs)
- Category: Airplane
- Serial number: 2558R
- Airframe hours: 4006
- Engines: P&W R1340 600 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Sunniland Aircraft Sales, Inc.
- Registered owner: Sunniland Aircraft Sales, Inc
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, May 11, 1990, 4 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 56; commercial; airplane ratings: single-engine land, multi-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: center; flight hours: 7,000 total, 3,000 in this make and model, 6,700 as pilot in command, 150 in the last 90 days, 50 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 120° at 16 knots
- Visibility: 7 statute miles
- Lowest ceiling: 3,000 ft broken
- Temperature: 82 °F, dew point 72 °F
- Altimeter: 29.00 inHg
- Observed at: VRB, 10 nm away

## 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 19900526017569A](https://openairdocs.org/incident/19900526017569A), May 26, 1990: Ayres S2RR1340REST, Vero Beach, FL, Substantial damage. Severe vibration,dumped load. Secured engine,hit trees on landing. Prop counterweight shaft broke. Improper repair.

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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