Boeing 737-200 N9063U

Summary

On 28 April 1997 at about 18:00 local time, a Boeing 737-200 registered N9063U was involved in an incident near Chicago, Illinois, United States. 58 people were on board and 2 had minor injuries. The aircraft was slightly damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

28 April 1997 at 18:00

Classification

Incident

Location

Chicago, Illinois, United States

Nearest airport

Chicago Ohare (ORD)

Coordinates

Not recorded

Aircraft

Boeing 737-200

Registration

N9063U

Category

Airplane

Engines

2

Operator

Not recorded

Operating rule

Part 121: Air Carrier

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Unknown → Philadelphia

Aircraft damage

Minor

Weather

VMC

Light

Day

NTSB number

CHI97IA117

2 people had minor injuries.

inadequate nickel plating was applied to the compressor disk during the rework process at the operator's overhaul facility, which resulted in a brittle fracture in the disk and an uncontained engine failure. A factor was the operator's lack of written procedures and guidance for personnel on the NiCad plating line, along with their failure to supply a method of measuring the thickness of nickel applied.

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

Read the full NTSB narrative

The airplane experienced an uncontained failure of the 10th stage compressor disk in the right engine. The flight crew aborted the takeoff, and an emergency evacuation was conducted after an engine fire was reported to the flight crew. Metallurgical inspection of the disk revealed that it had received insufficient nickel plating when it was reworked at the operator's facility 38 flight hours and 33 cycles prior to the incident. This resulted in cadmium embrittlement of the steel. The investigation revealed the operator had no written procedures to outline the process parameters and rectifier set-ups to be used during the NiCad plating process. NiCad plating line personnel also did not have any means of checking the thickness of the nickel plating during the plating process.

Quoted verbatim from the NTSB record.