- Date
- August 22, 1991, 16:04 local (23:04 UTC)
- Place
- Seattle, WA
- Injuries
- 11 minor, 376 uninjured
- Damage
- Minor damage
- Phase of flight
- Enroute
- Aircraft
- N604USBoeing 747-151
- Weather
- Visual (VMC) · Day
- Status
- Completed · report February 8, 1993
- Report
- Approved by Office Director
- FAA report
- 19910822046199I
- Case key
- 41348
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the incident.
On this page
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.
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
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.
Aircraft
- Registration
- N604US
- Reported as
- Boeing 747-151
- Category
- Airplane
- Serial number
- 19781
- Engine
- P&W JT9D-7A, 46,500 lbs thrust, turbo fan
- Damage
- Minor damage
- Fire
- In-Flight
- Flight
- Part 121
- Operator
- Northwest Airlines, Inc
- Airworthiness certificate
- Standard, Transport
- Departed
- KSEA · Seattle, WA
- Destination
- RJAA · Tokyo, OF
- Flight plan
- IFR
- Airport
- SEA · Seatac, runway 34R, 11,900 × 150 ft, asphalt
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 58
- Certificate
- Airline transport
- Airplane ratings
- Multi-engine land, Single-engine sea, Single-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Valid Medical--w/ waivers/lim
- Seat
- Left
- Flight hours
- 22,700 total · 2,700 in this make and model · 150 in the last 90 days · 50 in the last 30 days · 1 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 220° at 8 knots
- Visibility
- 50 statute miles
- Lowest ceiling
- None
- Temperature
- 79 °F, dew point 55 °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.
Other investigations on N604US · 2
Matched to the same aircraft by N-number and date.