# NTSB CEN11IA286: Cessna 560XL, N547CS, Abbeville, LA, April 8, 2011 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: April 8, 2011, 16:20 local (21:20 UTC) - Place: Abbeville, LA - Coordinates: 29.418056, -92.351112 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=29.4181&lon=-92.3511&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Flight control sys malf/fail](https://openairdocs.org/ntsb-events/333) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report November 5, 2012 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 78873 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN11IA286 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/78873/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=78873 - Page: https://openairdocs.org/ntsb/CEN11IA286 ## Probable cause The pitch trim control cable failed due to fatigue, rendering the elevator trim inoperative. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Flight control system: elevator tab control system](https://openairdocs.org/ntsb-findings/01022731): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [All aircraft, 37 cases](https://openairdocs.org/ntsb-findings/01022731/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute: Flight control sys malf/fail](https://openairdocs.org/ntsb-events/333) (defining event); cases with it: [All aircraft, 410 cases](https://openairdocs.org/ntsb-events/333/sequence.md) - [Emergency descent: Course deviation](https://openairdocs.org/ntsb-events/281); cases with it: [All aircraft, 52 cases](https://openairdocs.org/ntsb-events/281/sequence.md) ## Analysis During the initial climb and approaching the assigned altitude, the captain noticed an abnormal feel in the flight controls followed by the pitch trim annunciator light coming on. The captain disconnected the autopilot and felt the airplane’s nose immediately pitch up. The captain immediately corrected for the abnormal pressure and attempted to reduce the control forces via the electric and manual trim to no avail. The captain slowed the airplane to the speed at which it was trimmed and ran the checklist for a jammed elevator trim. The captain notified his company dispatch, declared an emergency with approach control, and landed the airplane uneventfully. A postincident examination showed that the elevator trim cable had failed due to fatigue. A laboratory examination showed slight wear on the individual cable strands. The cable had been installed at the time of manufacture and had accumulated 5,445.3 total hours. Following the examination, the airplane manufacturer determined that the cable required replacement with one made of improved rope wire material and issued a service bulletin requiring owners and operators to replace the elevator trim cable with the new cable within 300 hours or 6 months from receipt of the service bulletin. ## Factual narrative On April 8, 2011, about 1620 central daylight time, a Cessna 560XL, N547CS, while climbing after departure, experienced a loss of elevator trim control near Abbeville, Louisiana. The captain declared an emergency and diverted to the San Antonio International Airport (SAT), San Antonio, Texas, for an uneventful landing. The two airline transport rated pilots, the sole occupants on board the airplane, were not injured. The airplane was registered to and operated by CitationShares Sales Inc., of Greenwich, Connecticut, and doing business as CitationAir under the provisions of 14 Code of Federal Regulations Part 91 as a positioning flight. Visual meteorological conditions prevailed and an instrument flight rules (IFR) flight plan had been filed for the cross-country flight which had departed the Louis Armstrong New Orleans International Airport (MSY), New Orleans, Louisiana, at 1450, and was en route to the William P. Hobby Airport (HOU), Houston, Texas. According to the captain, the take off was normal and the climb was uneventful to 23,000 feet. About 1,000 feet below their cleared altitude, both pilots noticed an abnormal feel in the controls. Thinking perhaps the autopilot had disengaged, the captain verified that it was still connected. Approaching 23,000 feet the pitch trim annunciator came on. The captain disconnected the autopilot and felt the airplane’s nose immediately pitch up. The captain immediately controlled the abnormal pressure and attempted to reduce the control forces via the electric and manual trim to no avail. The pitch trim wheel spun without effect or friction. The captain slowed the airplane to the speed at which it was trimmed and ran the checklist for jammed elevator trim. The captain notified his company dispatch and declared an emergency with SAT approach control. The captain did a controllability check to insure no other control issues existed. He then flew a long final approach to an uneventful landing at SAT. A postaccident inspection of the elevator trim system revealed that the aft elevator trim cable had separated in two parts. The fractured cable was retained for further analysis. The cable pieces were examined in Wichita, Kansas, on June 16, 2011. The fracture occurred 11 inches from the roller chain that tracked through the elevator trim actuator. Using a scanning electron microscope, the examination showed fatigue failures in the individual wire strands. At high magnification, slight wear of the wire surfaces was observed. The cable was originally installed on the airplane at the time of manufacture. At the time of the incident, the cable had a total time of 5,445.3 hours. Cessna Aircraft determined that a cable with improved rope wire material was required. On April 9, 2012, they issued Service Bulletin SB560XL-27-34 requiring replacement of the elevator trim cable with the new cable within 300 hours or 6 months from receipt of the service bulletin. ## Aircraft - Registration: N547CS (not matched to a registry record) - Reported make and model: CESSNA 560XL - Category: Airplane - Serial number: 560-5542 - Airframe hours: 5346 - Engines: P&W CANADA 545b 3911 lbs thrust turbo fan; P&W CANADA 545b 3911 lbs thrust turbo fan - Damage: No damage - Flight: Positioning, Part 91 - Operator: CitationShares Sales Inc.,, doing business as CitationAir - Registered owner: CitationShares Sales Inc., - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, March 9, 2011 - Departed: MSY, New Orleans, LA - Destination: SAT, San Antonio, TX - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 68; injuries: none; airline transport; airplane ratings: multi-engine land; medical: class 1, without waivers/limitations; last flight review November 22, 2010; seat: left; flight hours: 17,769 total, 2,271 in this make and model, 9,913 as pilot in command, 83 in the last 90 days, 34 in the last 30 days - Co-pilot; age 33; injuries: none; airline transport, commercial; airplane ratings: multi-engine land, single-engine land; medical: class 1, without waivers/limitations; last flight review October 20, 2010; seat: right; flight hours: 4,068 total, 456 in this make and model, 957 as pilot in command, 87 in the last 90 days, 15 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 14 knots, gusting 17 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 81 °F, dew point 72 °F - Altimeter: 29.95 inHg - Observed at: 0R3 ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Incident 20110408006229I](https://openairdocs.org/incident/20110408006229I), Apr 8, 2011: Cessna 560XL, San Antonio, TX, No damage. Aircraft was cleared for 23000. At 22OOO an abnormal feeling in the controls were noticed. At 23000 the pitch trim annunciator came on. After identifying the… ## Docket (5 files) The files NTSB released with the investigation on September 5, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=78873. 1.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 809 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40376134&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - CitationAir Report and Photos of Broken Elevator Trim Cable (item 2, .PDF, 282 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40376133&FileExtension=.PDF&FileName=CitationAir%20Report%20and%20Photos%20of%20Broken%20Elevator%20Trim%20Cable-Master.PDF - Party Form, Cessna Aircraft (item 3, .PDF, 256 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40376136&FileExtension=.PDF&FileName=Party%20Form,%20Cessna%20Aircraft-Redacted.PDF - Party Form, CitationAir (Operator) (item 4, .PDF, 81 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40376139&FileExtension=.PDF&FileName=Party%20Form,%20CitationAir%20(Operator)-Redacted.PDF - Cessna Aircraft Service Bulletin, Elevator Trim Cable Replacement (item 5, .PDF, 72 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40376140&FileExtension=.PDF&FileName=Cessna%20Aircraft%20Service%20Bulletin,%20Elevator%20Trim%20Cable%20Replacement-Master.PDF 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. --- 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.