# NTSB SEA89IA042: Fairchild SA-227-AC, N386PH, Seattle, WA, January 23, 1989

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: January 23, 1989, 13:44 local (21:44 UTC)
- Place: Seattle, WA
- Coordinates: 47.440521, -122.279129 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.4405&lon=-122.2791&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 14 uninjured
- Status: Completed, report August 26, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 40943
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA89IA042
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40943/pdf
- Page: https://openairdocs.org/ntsb/SEA89IA042

## Probable cause

INOPERATIVE NOSEWHEEL STEERING DUE TO IMPROPER MAINTENANCE. CONTRIBUTING TO THE INCIDENT WAS THE LACK OF ADEQUATE MAINTENANCE INFORMATION AVAILABLE IN THE AIRCRAFT MANUALS.

## Sequence of events

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

- Airframe/component/system failure/malfunction, takeoff - roll/run
  - landing gear,steering system - inoperative (cause)
  - maintenance,installation - improper, company maintenance personnel (cause)
  - acft/equip,inadequate aircraft manuals, manufacturer (contributing factor)
- Loss of control - on ground/water, takeoff - aborted
  - directional control - not possible (cause)

## Analysis

WHILE ON TAKEOFF ROLL, THE CPT TURNED THE ELECTRIC NOSE WHEEL STEERING OFF. THE FIRST OFFICER, FLYING THE ACFT, ANNOUNCED AN UNCOMMANDED RIGHT YAW. THE CPT TOOK THE CONTROLS BUT WAS NOT ABLE TO BRING THE ACFT TO A HALT BEFORE DEPARTING THE SIDE OF THE RUNWAY. POST MISHAP TESTS REVEALED A MALFUNCTION OF THE NOSE WHEEL STEERING DUE TO IMPROPER REPLACEMENT OF VALVES IN THE HYDRAULIC STEERING ACTUATOR UNIT.

## Aircraft

- Registration: [N386PH](https://openairdocs.org/deregistered/N386PH-2012-07-16), registration cancelled 2012-07-16, S/N AC-597, built 1984 (OpenAirDocs)
- Reported make and model: FAIRCHILD SA-227-AC
- Registry model: [Fairchild SA227-AC](https://openairdocs.org/model/fairchild-sa227-ac) (registry code 3377509) (OpenAirDocs)
- Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs)
- Category: Airplane
- Serial number: 597
- Airframe hours: 8404
- Engines: GARRETT TPE-331 1000 horsepower turbo prop; GARRETT TPE-331 1000 horsepower turbo prop
- Damage: Minor damage
- Flight: Part 135
- Operator: Horizon Air
- Registered owner: First Security Bank Of Utah
- Airworthiness certificate: Standard, Normal
- Last inspection: Continuous airworthiness, January 14, 1989, 52 hours before
- Destination: PDX, PORTLAND, OR
- Flight plan: IFR
- Airport: SEA, Seatac, runway 16, 11,900 × 150 ft, concrete

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 32; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 6,500 total, 3,000 in this make and model, 5,000 as pilot in command, 240 in the last 90 days, 80 in the last 30 days, 5 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 160° at 7 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 37 °F, dew point 30 °F
- Altimeter: 30.00 inHg
- Observed at: SEA

## FAA reports on this event (1)

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

- [Incident 19890123005429I](https://openairdocs.org/incident/19890123005429I), Jan 23, 1989: Swrngn SA227AC, Seattle, WA, Minor damage. Aborted takeoff when nose wheel made uncommanded right turn. Veered off runway into mud. Cause 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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