# NTSB ANC08IA033: Fairchild SA227-AC, N41NE, Dutch Harbor, AK, January 18, 2008 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: January 18, 2008, 12:45 local (16:45 UTC) - Place: Dutch Harbor, AK - Coordinates: 53.906944, -166.549163 - Nearby events: https://openairdocs.org/map.md?lat=53.9069&lon=-166.5492&mi=10 - Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping) - Defining event: [Taxi-to runway: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report May 28, 2008 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Anchorage FSDO-03 - NTSB case key (mKey): 67423 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC08IA033 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/67423/pdf - Page: https://openairdocs.org/ntsb/ANC08IA033 ## Probable cause The disengagement of the rudder control cable and loose rudder cable retaining pins. A factor contributing to the accident was a wind gust. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Flight control system: rudder control system](https://openairdocs.org/ntsb-findings/01022720): Aircraft › Aircraft systems · Failure (probable cause) - [Misc hardware: fasteners](https://openairdocs.org/ntsb-findings/01071430): Aircraft › Fluids/misc hardware · Not specified (probable cause) - [Wind: gusts](https://openairdocs.org/ntsb-findings/03034045): Environmental issues › Conditions/weather/phenomena · Effect on equipment (probable cause) ## Analysis The pilot of the nonscheduled cargo flight reported that during taxi for takeoff the airplane encountered a 68-knot wind gust, and he returned to the gate to examine the rudder. Finding no damage, he continued the flight. After takeoff, the pilot said there was very little left rudder control. An examination of the rudder was made after the airplane landed at its destination. From the pilot's rudder pedals, the rudder is controlled by a cable which makes a 180-degree turn toward the tail via two phenolic pulleys. Each pulley has two guard pins, which keep the cable from jumping off the pulleys if the cable becomes slack. The inspection showed that the cable had jumped off the upper pulley. The pulley's upper guard pin had retracted, and did not prevent the cable from jumping off the pulley. The guard pin has a perforated and deformed end, giving it a spring action which secures the pin after passing through the holes on either side of the pulley bracket. No service difficulty reports were found for the pins, and the pins do not have any service life limits. An examination of the operator's other, similar model airplanes, showed that several of their guard pins had also retracted. Evidence suggests that the pin's locking action becomes weakened and ineffective by repeated use. The operator submitted a service difficulty report, and as a result of this incident, the manufacturer has published service letters 226-SL-037, 227-SL052, and CC7-SL-045. The service letters indicate that the pins should be inspected, and that all pins should be replaced with improved pins, and secured with cotter pins. ## Factual narrative On January 18, 2008, about 1245 Alaska standard time, a Fairchild SA227-AC airplane, N41NE, had a rudder malfunction after encountering a severe wind gust during taxi for takeoff at the Dutch Harbor Airport, Dutch Harbor, Alaska. The airplane was being operated by Peninsula Airways Inc., Anchorage, Alaska, as an instrument flight rules (IFR) nonscheduled cargo flight under Title 14, CFR Part 121. The airline transport certificated pilot and the first officer were not injured. Visual meteorological conditions prevailed at the departure airport, and an instrument flight rules flight plan was filed and activated. The airplane departed Dutch Harbor, and landed at the Ted Stevens International Airport, Anchorage, without incident. In a written statement, the pilot reported that during taxi for takeoff at Dutch Harbor, the airplane encountered a 68 knot wind gust. He said that they returned to the gate to examine the rudder because this airplane model has a history of rudder damage when encountering extreme wind gusts. Finding no damage, they elected to continue the flight. During initial climb after takeoff, the pilot said there was little, if any, left rudder control. The flight continued to the destination and landed without incident. The airplane was examined by an FAA air safety inspector. From the pilot's position, the rudder is controlled by a cable which makes a 180 degree turn toward the tail via two phenolic pulleys. Each of the pulleys has two guard pins (P/N: NAS427W18), which keep the cable from jumping off the pulleys if the cable becomes slack. During the inspection, the inspector reported that the cable had jumped off the upper pulley, disabling the rudder system. She noted that the pulley's guard pin was retracted, and did not prevent the cable from being dislodged. The guard pin is a hollow roll pin with a perforated and deformed end, giving it a spring action which secures the pin after passing through the holes on either side of the pulley bracket. She said there are no current service difficulty reports on file for the pins, and they do not have any service life limits. During an examination of all the same model airplanes in the operator's fleet, maintenance personnel found several guard pins that had come loose and retracted from their respective brackets. According to the director of maintenance for the operator, it appears that the pin's locking action becomes weakened by repeated use. The operator elected to replace all the pins in the operator's fleet, and submitted a service difficulty report to the FAA. As a result of this incident, the manufacturer has published service letters 226-SL-037, 227-SL052, and CC7-SL-045. The service letters require at the next scheduled access that the pins be inspected, and that all pins (P/N NAS427K18) be replaced with pins (P/N NAS427W18), and secured with cotter pins (P/N MS24665-132). ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Taxi-to runway: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) (defining event) - [Taxi-to runway: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) ## Aircraft - Registration: [N41NE](https://openairdocs.org/deregistered/N41NE-2010-07-23), registration cancelled 2010-07-23, S/N AC741B, built 1989 (OpenAirDocs) - Reported make and model: Fairchild SA227-AC - Registry model: [Fairchild SA227-AC](https://openairdocs.org/model/fairchild-sa227-ac) (registry code 3377509) (OpenAirDocs) - Registry engine: [AiResearch TPE331 series](https://openairdocs.org/engine/airesearch-tpe331-series) (registry code 01514, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 741B - Airframe hours: 36207 - Engines: Honeywell TPE331-11U 1000 horsepower turbo prop - Damage: No damage - Flight: Part 121 - Registered owner: Peninsula Airways Inc - Airworthiness certificate: Standard, Normal - Last inspection: Continuous airworthiness, January 1, 2008 - Departed: L-2G, Dutch Harbor, AK - Destination: PANC, Anchorage, AK - Flight plan: IFR - Airport: L2G, Dutch Harbor, runway 12, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 28; injuries: none; commercial, flight instructor, airline transport; airplane ratings: single-engine land, multi-engine land, single-engine sea; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review August 1, 2007; seat: left; flight hours: 7,307 total, 5,002 in this make and model, 225 in the last 90 days, 72 in the last 30 days, 3 in the last 24 hours - Co-pilot; age 26; injuries: none; commercial, airline transport; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review April 1, 2007; seat: right; flight hours: 2,904 total, 1,407 in this make and model, 298 in the last 90 days, 119 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 130° at 37 knots, gusting 47 - Visibility: 9 statute miles - Lowest ceiling: 3,300 ft overcast - Temperature: 45 °F, dew point 36 °F - Observed at: PAUD ## 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 20080118010589I](https://openairdocs.org/incident/20080118010589I), Jan 18, 2008: Swrngn SA227AC, Unalaska, AK, No damage. (-23) On January 18, 2008, an airplane N41NE, SA-227 declared an emergency as a result of flight control failure. During taxiing in dutch harbor with 68 knots… 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.