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Aviation safety reports, made easier to study

NTSB Reports is an independent research and search tool for public aviation accident and incident records. It brings NTSB aviation reports, structured fields, docket files, extracted figures, photos, videos, and update history into one searchable interface.

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August 22, 1991 · Boeing 747-151 · N604US

Seattle, WA

Overview

Report Status
Probable Cause
Event Type
Incident
Date
August 22, 1991
Injury Outcomes
11 injuries (11 minor injuries), 376 uninjured
Location
Seattle, WA
Aircraft
Boeing 747-151
Tail Number
N604US
Operator
Northwest Airlines
Injuries
Minor
Aircraft Damage
Minor
NTSB Number
SEA91IA219

THE NO 4 ENGINE CAUGHT FIRE DURING CLIMB AFTER TAKEOFF AND THE CREW ACTIVATED THE ENGINE FIRE EXTINGUISHER SYSTEM, DUMPED FUEL, AND RETURNED TO THE ARPT FOR AN EMERGENCY LANDING. THE NO 4 ENGINE FIRE AND A GRASS FIRE AT THE RWY T/D ZONE WERE EXTINGUISHED BY ARPT CFR CREW. AN EMERGENCY EVAC WAS CONDUCTED FROM THE LEFT SIDE AFTER THE ACFT STOPPED ON THE RWY. THE L5 EMERGENCY DOOR AND SLIDE FAILED TO DEPLOY FOR THE EVAC. EXAM OF THE ENGINE REVEALED EVIDENCE OF FUEL LEAK FROM THE MAIN FUEL CONTROL UNIT.

NTSB Probable Cause

A FIRE IN THE NUMBER 4 ENGINE, RESULTING FROM A FUEL LEAK AT THE MAIN FUEL CONTROL UNIT, DUE TO IMPROPER MAINTENANCE BY UNKNOWN/UNDETERMINED PERSON. THE L5 EMERGENCY EXIT FAILED TO OPERATEE DUE TO A BROKEN PLASTIC PULLEY GUARD IN THE SLIDE RELEASE MECHANISM.

Full Narrative

THE NO 4 ENGINE CAUGHT FIRE DURING CLIMB AFTER TAKEOFF AND THE CREW ACTIVATED THE ENGINE FIRE EXTINGUISHER SYSTEM, DUMPED FUEL, AND RETURNED TO THE ARPT FOR AN EMERGENCY LANDING. THE NO 4 ENGINE FIRE AND A GRASS FIRE AT THE RWY T/D ZONE WERE EXTINGUISHED BY ARPT CFR CREW. AN EMERGENCY EVAC WAS CONDUCTED FROM THE LEFT SIDE AFTER THE ACFT STOPPED ON THE RWY. THE L5 EMERGENCY DOOR AND SLIDE FAILED TO DEPLOY FOR THE EVAC. EXAM OF THE ENGINE REVEALED EVIDENCE OF FUEL LEAK FROM THE MAIN FUEL CONTROL UNIT.

Flight

Event TypeIncident
Event Time16:04 PDT
Nearest AirportSEATAC (0nm N)
Runway34R
Runway Length11900 ft
Runway Width150 ft
Flight Plan FiledIFR
Aircraft FireIflt
Aircraft ExplosionIflt

Aircraft

AircraftBoeing 747-151
Tail NumberN604US
Aircraft CategoryAir
DamageMinor
OperatorNorthwest Airlines
Operating RulePart 121
Engines4
Engine TypeTurbofan
Engine DetailsP&W · JT9D-7A · Turbofan · 46500
Seats422

People & Injuries

Injury Summary11 injuries (11 minor injuries), 376 uninjured
Fatal0
Serious0
Minor11
Uninjured376
Total387
Crew 1Age 58 · First Class

Conditions

ConditionsVMC
LightDaylight
Wind220° @ 8 kt
Visibility50 sm
CeilingNone
Temperature / Dew Point55
Altimeter30.00 inHg
Observation Time23:35
Weather SourceWFAC

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Appendix: Source Data