Fairchild SA-227AC N174SW

Summary

On 5 April 1994 at about 01:15 local time, a Fairchild SA-227AC registered N174SW, operated by Skywest Airlines Inc., was involved in an incident near Ontario, California, United States. 12 people were on board and one 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

5 April 1994 at 01:15

Classification

Incident

Location

Ontario, California, United States

Coordinates

34.0192, -117.5794

Aircraft

Fairchild SA-227AC

Registration

N174SW

Category

Airplane

Engines

2

Operator

Skywest Airlines Inc.

Operating rule

Part 135: Air Taxi & Commuter

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Los Angeles → Yuma

Aircraft damage

Minor

Weather

VMC

Light

Day

NTSB number

LAX94IA181

1 person had minor injuries.

the failure of maintenance personnel to detect a crack in the windscreen which exceeded the operational limits for pressurized flight. A factor in the accident was the inadequacy of the inspection method published by the manufacturer.

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

Read the full NTSB narrative

The aircraft was climbing at 1,000 feet per minute to a cruising altitude of 21,000 feet. Passing 19,800 feet, a loud 'bang' was heard and the captain was partially sucked through the broken left side window. After about 4 seconds, he was able to pull himself back into the aircraft unassisted. He declared an emergency and landed the aircraft without further incident. A review of the maintenance records revealed that an applicable airworthiness directive requiring an inspection of the windows was complied with within the last 143.8 flight hours. The technical representative for Fairchild stated that maintenance personnel who conducted the AD inspection and service bulletin inspections may have failed to detect the crack, due to the subtle inspection procedures employed. The approved inspection procedures allow for two methods: 1) removal of the outer frame retainer for direct viewing of the screw holes, and 2) using a 90-degree prism seated in mineral oil for an indirect view of the screw holes. The airline was using the second method.

Quoted verbatim from the NTSB record.