Status:	Final
Date:	15 FEB 1983
Time:	11:02
Type:	de Havilland Canada DHC-6 Twin Otter 300
Operator:	Sierra Pacific Airlines
Registration:	N361V
C/n / msn:	361
First flight:	1973
Total airframe hrs:	4767
Engines:	2 Pratt & Whitney Canada PT6A-27
Crew:	Fatalities: 0 / Occupants: 2
Passengers:	Fatalities: 0 / Occupants: 6
Total:	Fatalities: 0 / Occupants: 8
Airplane damage:	Destroyed
Airplane fate:	Written off (damaged beyond repair)
Location:	1,7 km (1.1 mls) S of Hailey-Sun Valley Airport, ID (SUN) (United States of America)
Phase:	Approach (APR)
Nature:	Domestic Scheduled Passenger
Departure airport:	Boise Air Terminal (Gowen Field), ID (BOI/KBOI), United States of America
Destination airport:	Hailey-Sun Valley Airport, ID (SUN/KSUN), United States of America
Flightnumber:	868

Narrative:
The Twin Otter, operating on a flight for Transwestern, approached Hailey runway 31 at an altitude of 800 feet when the captain reduced power. Suddenly, the aircraft nosed over and descended steeply. The pilot tried to control the descent by adding power. The plane crash-landed on a highway, veered off and struck a 4 feet high snow bank.

PROBABLE CAUSE: "The in-flight loss of elevator control following separation of the control rod from the torque tube at a connection where the company's maintenance department had used a non-standard, unsecured bolt, which the company's inspection department had failed to detect. Contributing to the accident was the company's failure to maintain the separation of maintenance and inspection functions required by the maintenance program approved by the Federal Aviation Administration, and the failure of the FAA to detect the company's deviation from approved maintenance procedures during surveillance inspection."

Events:

Sources:
» Location of Commercial Aircraft Accidents/Incidents Relative to Runways / FAA, Office of Safety Oversight (DOT/FAA/AOV 90-1)
» NTSB-AAR-84-03