Aircraft Accident/Incident Report

Kansas City, Missouri 64153
Thursday, May 19, 2005 9:25 CDT

NTSB Narrative Summary Released at Completion of Accident

The airplane sustained minor damage as a result of an uncontained failure of the left engine. Examination of the airplane revealed that the left engine's fan spinner was completely missing, and the forward fan blade retainer was missing a 90-degree section of the bolt flange. Several pieces of the fan spinner were recovered within the cowl. The NTSB's examination of the fan blade forward retaining ring revealed features indicative of overstress failure which originated on the forward face adjacent to a linear impression. The length and location of the linear impression corresponded to the corner on one of the bolt lugs on the aft side of the spinner. The linear impression contained evidence of fretting damage. The inside radius between the retaining ring's raised lip, and the flange was within the range specified by the manufacturer. The spinner's bolt lugs had a sharp outside corner where the spinner would interface with the radius on the retaining ring. The forging drawing for this part did not specify a radius; however, a manufacturer's representative indicated that an engineering drawing for the spinner specified that exterior corners have an edge break with a radius between 0.005 and 0.020 inches. The combination of the radius on the retaining ring, and the sharp edge on the aft side of the spinner, resulted in an interference when the parts were assembled. The manufacturer's examination of the retained parts indicated the presence of high cycle fatigue on both the spinner and the fan blade retaining ring. Three dimensional finite element analysis of the fan spinner, and forward fan blade retaining ring predicted a reduced low cycle fatigue life. As a result of this investigation, the manufacturer initiated a one-time, on-wing eddy current inspection of all the one-piece fan spinners to be accomplished within 18 months or 2,000 hours. The manufacturer also initiated a re-design of the fan spinner, and indicated that the one-piece fan spinners will be removed from service by the end of 2010.

NTSB Probable Cause Narrative

The fatigue failure during cruise flight of the fan spinner and forward fan retaining ring due to an interference between the mating parts resulting from the inadequate design by the manufacturer.

Event Information

Type of Event Incident
Event Date 5/19/2005
Event Day of the Week Thursday
Time of Event 925
Event Time Zone Central Daylight Time
Event City Kansas City
Event State MISSOURI
Event Country --
Zipcode of the event site 64153
Event Date Year 2005
Event Date Month 5
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 --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness --
Investigator's weather source Weather Observation Facility
Time of the weather observation 1053 Central Daylight Time
Direction of event from weather observation facility (degrees) --
Weather Observation Facility ID MCI
Elevation of weather observation facility --
Distance of event from weather observation facility (units?) --
Time Zone of the weather observation CDT
Lighting Conditions Day
Lowest Ceiling Height --
Lowest Non-Ceiling Height --
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 26
Dew Point at event time (in degress fahrenheit) 17
Wind Direction (degrees magnetic) 220
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) 8
Wind Velocity Indicator --
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 29.84
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report METAR KMCI 191253Z 22004KT 6SM BR CLR 19/18 A2983
Event Highest Injury None
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal --
Injury Total Minor --
Injury Total None 54
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 21770
NTSB Notification Source FAA
NTSB Notification Date May 19 2005 12:00AM
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Jul 25 2007 12:22PM
User who most recently changed record NTSB\lema
Basic weather conditions Visual Meteorological Cond
FAA District Office St. Louis, Missouri

Aircraft Involved

Aircraft #1

Aircraft Registration Number N814HK
NTSB Number CHI05IA116
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 121: Air Carrier
Type of Flight Plan filed IFR
Flight plan Was Activated? Yes
Damage Minor
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Embraer
Aircraft Model EMB-145LR
Aircraft Series Identifier --
Aircraft Serial Number 145046
Certified Max Gross Weight 48721
Aircraft Category Airplane
Aircraft Registration Class --
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 53
Number of Engines 2
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Continuous Airworthiness
Date of Last Inspection Apr 1 2005 12:00AM
Airframe hours since last inspection --
Airframe Hours 18852
ELT Installed --
ELT Activated --
ELT Aided Location of Event Site --
ELT Type --
Aircraft Owner Name American Eagle Airlines Inc.
Aircraft Owner Street Address 4333 Amon Carter Blvd
Aircraft Owner City Fort Worth
Aircraft Owner State TX
Aircraft Owner Country USA
Aircraft Owner Zipcode 76155
Operator is an individual? No
Operator Name TRANS STATES AIRLINES INC
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address 11495 Natural Bridge Road, Suite 340
Operator City Bridgeton
Operator State MO
Operator Country USA
Operator Zip code 63044
Operator Code RAIA
Owner has at least one certificate --
Other Operator of large aircraft? --
Certified for Part 133 or 137 Operation --
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not Scheduled
Indicates Domestic or International Flight Domestic
Operator carrying Pax/Cargo/Mail Passenger Only
Type of Flying (Per_Bus / Primary) --
Second Pilot on Board Yes
Departure Point Same as Event No
Departure Airport Code STL
Departure City ST LOUIS
Departure State MO
Departure Country USA
Departure Time 1000
Departure Time Zone CDT
Destination Same as Local Flt --
Destination Airport Code DEN
Destination City DENVER
Destination State CO
Destination Country USA
Specific Phase of Flight Cruise
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record May 30 2007 5:46PM
User who most recently changed record DINC
Since inspection or accident Time of Accident
Event Location Runway Number and Location NA
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --