Date:	05-NOV-1992
Time:	02:30
Type:	Piper PA-31T Cheyenne II
Owner/operator:	Ameriflight Inc.
Registration:	N131AF
C/n / msn:	31T-7820005
Fatalities:	Fatalities: 0 / Occupants: 1
Other fatalities:	0
Aircraft damage:	None
Category:	Accident
Location:	Medford, OR -   United States of America
Phase:	En route
Nature:	Unknown
Departure airport:	Portland, OR (PDX)
Destination airport:	Oakland, CA (OAK)
Investigating agency:	NTSB

Narrative:
DURING CRUISE FLIGHT AT FLIGHT LEVEL 230, THE AIRPLANE SUDDENLY PITCHED UP AND THE AUTOPILOT DISENGAGED. THE PILOT WAS UNABLE TO CONTROL THE AIRPLANE WITH THE CONTROL YOKE. USING POWER AND TRIM CONTROL, HE FINALLY REGAINED CONTROL OF THE AIRPLANE AND MADE AN EMERGENCY LANDING AT SACRAMENTO WITHOUT FURTHER INCIDENT. INVESTIGATION REVEALED THAT THE THREADED PORTION OF THE ROD END BEARING, P/N 49261-02, HAD SEPARATED AT THE POINT WHERE THE THREADS ARE INSERTED INTO THE AFT END OF THE ELEVATOR CONTROL TUBE ASSEMBLY, P/N 40847-07. THE ELEVATOR CONTROL TUBE CONNECTS TO THE ELEVATOR PITCH HORN. METALLURGICAL EXAMINATION SHOWED THAT THE SEPARATION WAS DUE TO A FATIGUE FAILURE. THE AIRCRAFT HAD BEEN INSPECTED AT 37 HRS AND 134 HRS BEFORE THE INCIDENT IN ACCORDANCE WITH AN APPROVED AIRCRAFT INSPECTION PROGRAM. NEITHER INSPECTION SPECIFICALLY ADDRESSED AN INSPECTION OF THE ELEVATOR CONTROL TUBE ASSEMBLY.

Probable Cause: FATIGUE FAILURE OF THE ELEVATOR CONTROL TUBE ROD END BEARING RESULTING IN A LOSS OF ELEVATOR CONTROL.

NTSB: https://www.ntsb.gov/_layouts/ntsb.aviation/brief.aspx?ev_id=20001211X16054&key=1

Safety recommendation A-93-110 issued 31 August 1993 by NTSB to FAA
Safety recommendation A-93-111 issued 31 August 1993 by NTSB to FAA
Safety recommendation A-93-112 issued 31 August 1993 by NTSB to FAA
Safety recommendation A-93-113 issued 31 August 1993 by NTSB to FAA

Date/time	Contributor	Updates
23-Oct-2016 16:02	harro	Added
23-Oct-2016 16:04	harro	Updated [Aircraft type, Cn, Damage]
06-Aug-2017 19:42	TB	Updated [Aircraft type]
04-Nov-2018 08:43	ASN Update Bot	Updated [Time, Operator, Nature, Departure airport, Destination airport, Source, Damage, Narrative, Accident report, ]