Bombardier CL-600-2B19 N17337

Summary

On 25 January 2007 at about 23:47 local time, a Bombardier CL-600-2B19 registered N17337, operated by Mesa Airlines Inc, was involved in an incident near Cripple Creek, Colorado, United States. 54 people were on board and nobody was injured. The aircraft was slightly damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

25 January 2007 at 23:47

Classification

Incident

Location

Cripple Creek, Colorado, United States

Coordinates

38.7397, -105.3042

Aircraft

Bombardier CL-600-2B19

Registration

N17337

Category

Airplane

Engines

2

Operator

Mesa Airlines Inc

Operating rule

Part 121: Air Carrier

Phase of flight

Not recorded

Route

Denver → Phoenix

Aircraft damage

Minor

Weather

VMC

Light

Day

NTSB number

DEN07IA055

Nobody was injured.

A fatigue fracture, which resulted in the separation of the No.1 engine fan disk. Contributing factors in the accident were the operators' maintenance personnel lack of training to be able to detect arc-out damage on the fan disk, and the fan disk manufacturer's inadequate electro-chemical etch match marking process of the fan disk to forward fan shaft that allowed for the initiation of a fatigue point that was undetected at the time of original manufacture.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

While climbing through FL 240, the No. 1 engine experienced a fan disk separation, which resulted in the separation of the inlet, fan rotor assembly, the fan containment case, and portions of the thrust reverser. The airplane reversed course and landed without further incident. Postincident examination revealed minor damage to the aft portion of the fuselage and empennage. An examination of the remaining airplane systems revealed no anomalies. Portions of the fan disk were recovered and examination of the fan disk revealed fatigue striations emanating from the aft bore corner of the fan disk. The striations came from an area that exhibited characteristics consistent with arc-out damage, which was the result of improper assembly and marking procedures during the electrochemical etching process. This damage was not detected during the manufacturer's quality assurance process used by the manufacturer. Further, the operator did not detect this damage while conducting the inspections prescribed through required airworthiness directives because the inspection procedures required were not detailed enough to detect the arc-out damage and the maintenance personnel did not receive appropriate training. Following the incident, the manufacturer issued alert service bulletins and the FAA issued an airworthiness directive to resolve these issues.

Quoted verbatim from the NTSB record.