# Accident 20000812014489A: Emb EMB120ER, San Angelo, TX, August 12, 2000

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: August 12, 2000, 13:03 local time
- Place: San Angelo, TX
- Airport: Mathis Field
- Phase of flight: Descent
- Operating rules: Air carrier (Part 121)
- Operator: C2XA
- Location: 31.6107° N, 100.5509° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=31.6107&lon=-100.5509&mi=10
- Aircraft: N16718 (not matched to a registry record)
- Reported make and model: EMB EMB120ER
- People aboard: 22
- Fatal injuries: 0
- Pilot flight hours: 5,500 total, 120 in this make and model, 120 in the last 90 days
- NTSB investigation: [NTSB FTW00IA228](https://openairdocs.org/ntsb/FTW00IA228) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/20000812014489A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

(-23) NO NARRATIVE (.4) 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 W                                                        HEN 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.

## The NTSB's investigation of this event (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB FTW00IA228](https://openairdocs.org/ntsb/FTW00IA228), Aug 12, 2000: Embraer EMB-120ER (N16718), San Angelo, TX, incident, no damage. Probable cause: the improper installation of the right elevator trim control wheel by company mechanics, which resulted in an elevator trim malfunction.

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.