# NTSB LAX88FA169: Piper PA-31-350, N3588Y, Hayward, CA, April 27, 1988

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Field investigation · Final report
- Date: April 27, 1988, 00:14 local (07:14 UTC)
- Place: Hayward, CA
- Coordinates: 37.669384, -122.079513 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.6694&lon=-122.0795&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report July 9, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 25829
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX88FA169
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/25829/pdf
- Page: https://openairdocs.org/ntsb/LAX88FA169

## Probable cause

PILOT'S FAILURE TO DETECT AN UNCOMMANDED PROPELLER FEATHERING PROCEDURES ESTABLISHED IN THE PILOT'S OPERATING HANDBOOK.

## Sequence of events

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

- Loss of engine power(partial) - mech failure/malf, approach - vfr pattern - base leg/base to final
  - propeller system/accessories,feathering system - failure,partial (cause)
  - emergency procedure - not followed, pilot in command (cause)
  - visual/aural perception, pilot in command (contributing factor)
- Forced landing, approach - vfr pattern - final approach
- In flight collision with object, landing - flare/touchdown
  - object - vehicle (contributing factor)
  - light condition - dark night (contributing factor)
  - terrain condition - roadway/highway (contributing factor)

## Analysis

UPON ARRIVING AT HIS DESTINATION THE PILOT BEGAN A VISUAL, NIGHT DESCENT TO HIS DESTINATION AIRPORT. AS THE AIRCRAFT DESCENDED THE PILOT REDUCED THE AIRSPEED AND DEPLOYED FLAPS. AS THE AIRCRAFT NEARED THE AIRPORT THE PILOT INCREASED THE FLAP ANGLE AND ADJUSTED THE PROPELLERS TO THE LANDING RPM AND THE AIRSPEED DECREASED. THE PILOT STATED THAT AT THIS TIME HE HEARD A NOISE THAT SOUNDED LIKE A FLUTTER WHICH HE THOUGHT WAS EMANATING FROM THE RIGHT ENGINE. FULL THROTTLE WAS APPLIED, BUT THE AIRSPEED CONTINUED TO DECREASE AND THE PILOT ELECTED TO LAND ON A FREEWAY. THE AIRCRAFT COLLIDED WITH A MOTOR VEHICLE ON TOUCHDOWN AND SLID TO A STOP. POST CRASH EXAM REVEALED THE RPM CONTROL LEVERS AND BELLRANKS TO BE IN THE HIGH RPM SETTINGS. THE LEFT PROP WAS FOUND IN THE FEATHERED POSITION.

## Aircraft

- Registration: [N3588Y](https://openairdocs.org/deregistered/N3588Y-1991-01-28), registration cancelled 1991-01-28, S/N 318052129 (OpenAirDocs)
- Reported make and model: PIPER PA-31-350
- Registry model: [Piper PA-31-350](https://openairdocs.org/model/piper-pa-31-350) (registry code 7103110) (OpenAirDocs)
- Category: Airplane
- Serial number: 318052129
- Airframe hours: 3355
- Engines: LYCOMING TSIO-540-J2BD 350 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Part 135
- Operator: Helicopters Unlimited
- Registered owner: Helicopters Unlimited Inc
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, April 22, 1988, 3 hours before
- Departed: CCB, UPLAND, CA
- Destination: HWD, HAYWARD, CA
- Flight plan: VFR
- Airport: HWD, Hayward Air Term., runway 28, 5,024 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 40; commercial, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 5,557 total, 30 in this make and model, 25 in the last 90 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Night/dark
- Wind: 260° at 6 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 63 °F, dew point 57 °F
- Altimeter: 29.00 inHg
- Observed at: OAK, 7 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 19880427011479A](https://openairdocs.org/incident/19880427011479A), Apr 27, 1988: Piper PA31350, Hayward, CA, Destroyed. Propellor feathered when governor failed. Emergency landing. Hit truck on freeway.

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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