Embraer EMB-120ER N16718

Summary

On 12 August 2000 at about 18:03 local time, a Embraer EMB-120ER registered N16718, operated by Continental Express Inc., was involved in an incident near San Angelo, Texas, United States. 23 people were on board and one had minor injuries. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

12 August 2000 at 18:03

Classification

Incident

Location

San Angelo, Texas, United States

Nearest airport

San Angelo Regional (SJT)

Coordinates

31.6107, -100.5509

Aircraft

Embraer EMB-120ER

Registration

N16718

Category

Airplane

Engines

2

Operator

Continental Express Inc.

Operating rule

Part 121: Air Carrier

Phase of flight

Not recorded

Route

Houston → San Angelo

Aircraft damage

Not recorded

Weather

VMC

Light

Day

NTSB number

FTW00IA228

1 person had minor injuries.

the improper installation of the right elevator trim control wheel by company mechanics, which resulted in an elevator trim malfunction.

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

Read the full NTSB narrative

The airplane was descending through 14,500 feet when an uncommanded disconnect of the autopilot occurred, and the airplane "abruptly" pitched up from 5 degrees nose down to 15 degrees nose up (pitch reversion). Simultaneously, the captain and first officer applied forward pressure on their control columns to regain control of the airplane. The airplane was re-established in a descent and the flight crew found that the airplane was controllable in the landing configuration. Subsequently, the flight landed without further incident. Post incident examination of the airplane revealed that the right elevator trim control wheel was improperly installed. The installation allowed the autopilot trim servo to request nose down trim until the trim tab actuators had reached their physical limits. The autopilot trim servo continued to request nose down trim, loading the elevator trim system cables, until the autopilot disconnected. During the examination, it was also noted that the trim tab deflections and cable tensions did not meet manufacturer specifications. Review of maintenance records revealed two instances when the elevator pitch trim system underwent maintenance. On April 14, 1998, the right side elevator trim control wheel was removed and reinstalled "while aligning stop arm into wheel." Continental Express reported that the trim tabs were adjusted during the maintenance. On August 11, 2000, the following maintenance write-up was recorded in the aircraft flight log: "Elev trim will not go full forward, stops at two units." The flight log indicated that the following corrective action was taken; "Lubed trim wheel for elev trim." Continental Express reported that the trim wheel was not removed during this corrective action.

Quoted verbatim from the NTSB record.