Aircraft Accident/Incident Report

Seattle, Washington 98188
Saturday, September 29, 1984 14:38 PDT

NTSB Narrative Summary Released at Completion of Accident

DURING CLIMBOUT, PASSING THRU 4000 FT MSL, THE ACFT EXPERIENCED A FAILURE OF THE #2 ENGINE. THE CREW REPORTED HEARING AN EXPLOSIVE SOUND FOLLOWED BY A DROP IN FUEL FLOW WITH N1 SPEED DECREASING TO 30% RPM ON THE #2 ENGINE. THE ACFT RETURNED TO SEATTLE FOR AN UNEVENTFUL LANDING. THE ENGINE EXHAUST TAIL CONE AND NUMEROUS TURBINE BLADES WERE LOCATED IN A RURAL AREA APRX 11 MILES SOUTH OF THE ARPT. INVESTIGATION REVEALED THE TURBINE STATOR SUPPORT STRUCTURE HAD WEAKENED BY SULFIDATION DUE TO EXHAUST GAGES ESCAPING THRU AN INSPECTION PORT. FAILURE OF THE PORT ALLOWED CONTACT WITH THE TURBINE BLADES, RESULTING IN BLADE ESCAPED AND SUBSEQUENT IMBALANCE.

NTSB Probable Cause Narrative

Not Yet Reported

Event Information

Type of Event Incident
Event Date 9/29/1984
Event Day of the Week Saturday
Time of Event 1438
Event Time Zone Pacific Daylight Time
Event City SEATTLE
Event State WASHINGTON
Event Country --
Zipcode of the event site 98188
Event Date Year 1984
Event Date Month 9
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport
Event Location Nearest Airport ID
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles 0
Degrees magnetic from airport 0
Airport Elevation 0
Weather Briefing Completeness Not pertinent
Investigator's weather source Weather Observation Facility
Time of the weather observation 1445 Pacific Daylight Time
Direction of event from weather observation facility (degrees) 340
Weather Observation Facility ID SEA
Elevation of weather observation facility 428
Distance of event from weather observation facility (units?) 11
Time Zone of the weather observation PDT
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 50
Air Temperature at event time (in degrees celsius) 24
Dew Point at event time (in degress fahrenheit) 2
Wind Direction (degrees magnetic) 290
Variable Wind Indicator Unknown
Wind Speed (knots) 5
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 172
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 5072
NTSB Notification Source --
NTSB Notification Date --
NTSB Notification Time 0
Fiche Number and/or location -used to find docket information 28156
Date of most recent change to record Jan 2 2001 9:15AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N613US
NTSB Number SEA84IA233
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 121: Air Carrier
Type of Flight Plan filed IFR
Flight plan Was Activated? --
Damage Minor
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name BOEING
Aircraft Model 747-200B
Aircraft Series Identifier 747-200B
Aircraft Serial Number 20358
Certified Max Gross Weight 800000
Aircraft Category Airplane
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 394
Number of Engines 4
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Continuous Airworthiness
Date of Last Inspection Jul 26 1984 12:00AM
Airframe hours since last inspection 689
Airframe Hours 44962
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name NORTHWEST AIRLINES, INC.
Aircraft Owner Street Address MINNIAPOLIS/ST. PAUL
Aircraft Owner City ST. PAUL,
Aircraft Owner State MN
Aircraft Owner Country
Aircraft Owner Zipcode 55111
Operator is an individual? --
Operator Name
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
Operator Code NWAA
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not Scheduled
Indicates Domestic or International Flight International
Operator carrying Pax/Cargo/Mail Passenger Only
Type of Flying (Per_Bus / Primary) Unknown
Second Pilot on Board Yes
Departure Point Same as Event Yes
Departure Airport Code SEA
Departure City SEATTLE
Departure State WA
Departure Country
Departure Time 1430
Departure Time Zone PDT
Destination Same as Local Flt --
Destination Airport Code SEL
Destination City SEOUL, KOREA
Destination State OF
Destination Country
Specific Phase of Flight Climb
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Dec 20 2002 12:42PM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length 0
Runway Width 0
Sight Seeing flight No
Air Medical Flight No
Medical Flight --