# NTSB MIA87LA126: Piper PA-31-350, N506ES, Miami, FL, April 3, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: April 3, 1987, 02:33 local (07:33 UTC)
- Place: Miami, FL
- Location: 25.7743° N, 80.1937° W: Placed by OpenAirDocs: center of Miami, FL, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=25.7743&lon=-80.1937&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 4 uninjured
- Status: Completed, report April 25, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 31888
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA87LA126
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/31888/pdf
- Page: https://openairdocs.org/ntsb/MIA87LA126

## Sequence of events

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

- Airframe/component/system failure/malfunction, climb - to cruise
  - propeller system/accessories,blade - loss,total (contributing factor)
  - propeller system/accessories,hub - failure,total (cause)
  - maintenance,major repair - not performed, company maintenance personnel (cause)
  - complacency, company maintenance personnel (cause)
- Forced landing, landing - flare/touchdown

## Analysis

DURING CLIMB TO CRUISE THE PILOT LOST ONE BLADE OF THE THREE BLADED RIGHT PROPELLER, DUE TO THE FAILURE OF THE HUB. EXAMINATION OF THE PROPELLER AND ENGINE REVEALED THAT THE CRANKSHAFT COUNTERWEIGHT BUSHINGS WERE NOT INSTALLED ALLOWING A HIGH FREQUENCY VIBRATION TO EXIST, CAUSING THE FAILURE OF THE HUB.

## Aircraft

- Registration: N506ES (not matched to a registry record)
- Reported make and model: PIPER PA-31-350
- Category: Airplane
- Serial number: 31-7952234
- Airframe hours: 3742
- Engines: LYCOMING LTIO-540-J2BD 350 horsepower reciprocating
- Damage: Substantial damage
- Flight: Positioning, Part 91
- Registered owner: Dolphin Aviation
- Airworthiness certificate: Standard, Normal
- Last inspection: AAIP, January 26, 1987, 20 hours before
- Departed: MIA, MIAMI, FL
- Destination: SRQ, SARASOTA, FL
- Flight plan: IFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 32; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 3,265 total, 123 in this make and model, 3,105 as pilot in command, 127 in the last 90 days, 9 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Night/dark
- Wind: 130° at 3 knots
- Visibility: 7 statute miles
- Lowest ceiling: none
- Temperature: 63 °F, dew point 52 °F
- Altimeter: 30.00 inHg
- Observed at: MIA, 6 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 19870403010459A](https://openairdocs.org/incident/19870403010459A), Apr 3, 1987: Piper PA31350, Miami, FL, Substantial damage. The propeller hub failed in fatigue. Aircraft landed safely. Unbalanced crankshaft set up high cycle stress mode.

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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