# NTSB WPR13LA102: Cessna 172RG, N6290V, Redmond, OR, January 18, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 17, 2013, 17:40 local (Jan 18, 2013, 01:40 UTC) - Place: Redmond, OR - Coordinates: 44.253887, -121.14833 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.2539&lon=-121.1483&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern downwind: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report June 11, 2014 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Cessna Aircraft Company, FAA - ADs cited in the narratives: [AD 2001-06-06](https://openairdocs.org/ad/2001-06-06) (OpenAirDocs) - NTSB case key (mKey): 86082 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR13LA102 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/86082/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=86082 - Page: https://openairdocs.org/ntsb/WPR13LA102 ## Probable cause Failure of the left main landing gear pivot assembly during the landing approach. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: landing gear actuator](https://openairdocs.org/ntsb-findings/01023233): Aircraft › Aircraft systems · Fatigue/wear/corrosion (probable cause); cases with it: [Cessna 172RG, 3 cases](https://openairdocs.org/ntsb-findings/01023233/cases.md?model=2072438), [All aircraft, 54 cases](https://openairdocs.org/ntsb-findings/01023233/cases.md) - [Inspection: scheduled/routine inspection](https://openairdocs.org/ntsb-findings/02061520): Personnel issues › Task performance · Maintenance personnel; cases with it: [Cessna 172RG, 2 cases](https://openairdocs.org/ntsb-findings/02061520/cases.md?model=2072438), [All aircraft, 167 cases](https://openairdocs.org/ntsb-findings/02061520/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern downwind: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [Cessna 172RG, 11 cases](https://openairdocs.org/ntsb-events/330/sequence.md?model=2072438), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Landing: Landing gear not configured](https://openairdocs.org/ntsb-events/095); cases with it: [Cessna 172RG, 15 cases](https://openairdocs.org/ntsb-events/095/sequence.md?model=2072438), [All aircraft, 584 cases](https://openairdocs.org/ntsb-events/095/sequence.md) - [Landing: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Cessna 172RG, 10 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=2072438), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis During the landing approach, the flight instructor and pilot undergoing instruction were unable to fully extend or retract the left main landing gear and, after multiple unsuccessful troubleshooting attempts, performed a gear-up landing. Postaccident examination revealed that the pivot assembly for the left main landing gear actuator had fractured and had separation features consistent with torsional fatigue. The Federal Aviation Administration previously issued an airworthiness directive (AD), which included an inspection of pivot assemblies for cracks, in accordance with a manufacturer's service bulletin (SB). The AD called for repetitive inspections of the pivot assembly if the airplane experienced a hard landing, and the SB recommended, in small print, full recompliance after a hard landing. The SB was complied with 12 years and 2,730 flight hours before the accident. The airplane was subsequently involved in a hard landing, and a reinspection was conducted; however, recompliance with the entire SB was not achieved as recommended in the SB, and the pivot failed 894 flight hours after the hard landing. ## Factual narrative On January 17, 2013, about 1740 Pacific standard time, a Cessna 172RG, N6290V, landed gear-up with the left main landing gear partially extended, at Roberts Field, Redmond, Oregon. Professional Air was operating the airplane under the provisions of 14 Code of Federal Regulations Part 91. The certified flight instructor (CFI) and pilot undergoing instruction were not injured. The airplane sustained substantial damage. The instructional flight departed Bend Municipal Airport, Bend, Oregon, about 1515. Night visual meteorological conditions prevailed, and no flight plan had been filed. During the landing approach into Bend, the pilot undergoing instruction was unable to fully extend or retract the left main landing gear. After multiple unsuccessful troubleshooting attempts, the CFI elected to divert to Redmond, retract the nose and right main landing gear, and perform a gear-up landing. During the landing roll, the airplane sustained substantial damage to the underside of the fuselage. Component Examination Postaccident examination revealed that the pivot assembly for the left landing gear actuator had broken at the fillet radius transition between the splined and non-splined portions of the pivot. The actuator assembly was sent to the Cessna Materials and Process Laboratory in Wichita, Kansas, for examination under the oversight of an engineer from the Federal Aviation Administration (FAA). Examination of the fracture surfaces revealed heavy smearing, typical of torsional fractures. The un-smeared pockets of the fracture surface displayed the presence of closely spaced fatigue striations, with the splined portion of the pivot displaying longitudinal cracking at the root of 36 of the 49 splines. The longitudinal spline cracking extended to the center of the pivot shaft, in a star pattern to depths of approximately 0.32 inches, effectively reducing the cross section of the shaft. A couple of these longitudinal cracks were broken open, revealing a fracture surface containing closely spaced fatigue striations. Material and chemical analysis as well as tensile testing was performed on the splined pivot, with results indicating that it met the engineering drawing requirements for its material type, 7175 aluminum. Landing Gear Service Bulletins On May 14, 2001, the FAA issued Airworthiness Directive AD 2001-06-06, which required the inspection of main landing gear pivot assemblies of certain Cessna 172 airplanes for cracks, in accordance with Cessna Service Bulletin SEB90-1 Revision 3. The service bulletin required replacement of any cracked main landing gear pivot assemblies on the affected airplanes, and the installation of new shaft bushings that were designed to enhance the service life of the pivot assembly. Cessna issued this service bulletin in March 1999. It stated that once complete, compliance was no longer necessary unless the airplane had experienced a landing gear overload condition, or if the brakes exhibited "spongy" operation that couldnot be attributed to brake component wear or improper servicing. The service bulletin stated that compliance with the inspection portion required about 10 hours of time per pivot assembly to complete. Maintenance Records Examination of the airplane's maintenance records revealed that SEB90-1 Revision 3 was complied with in June 2001, at a tachometer time of 5,544 hours. In May 2010, at a tachometer time of 7,379.6 hours, the airplane sustained a hard landing, requiring the removal of the propeller and engine for inspection, repair to the right wingtip, and a "hard landing inspection." No mention was made indicating that SEB90-1 had been complied with since that time. Additionally, the work order revealed that the total time spent performing the hard landing inspection was 4.02 hours. According to representatives from Cessna, the maintenance manual makes no mention of a hard landing inspection, and that items in such an exam are left to the discretion of the mechanic. The airplane's tachometer indicated 8,274 hours at the time of the most recent annual inspection, 2 days prior to the accident. Maintenance records indicated that the actuator was the original component, and had not been serviced or overhauled since the airplane's manufacture in 1980. A similar failure to that observed in the accident airplane occurred with a Cessna 172RG in Kissimmee, Florida, on November 8, 2011. See NTSB report number ERA12LA270 for further details. ## Aircraft - Registration: [N6290V](https://openairdocs.org/aircraft/N6290V), registered now, S/N 172RG0610, built 1980 (OpenAirDocs) - Reported make and model: CESSNA 172RG - Registry model: [Cessna 172RG](https://openairdocs.org/model/cessna-172rg) (registry code 2072438) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 172RG0610 - Year built: 1980 - Airframe hours: 8274 - Engines: LYCOMING O-360 180 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, January 15, 2013, 8 hours before - Departed: KBND, Bend, OH - Destination: RDM, Redmond, OR - Airport: RDM, Roberts Field, runway 10, 7,006 × 100 ft, asphalt - Equipment: Stall warning system, Auto-pilot ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 36; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review June 14, 2012; seat: left; restraint: 3-point; flight hours: 843 total, 45 in this make and model, 742 as pilot in command, 213 in the last 90 days, 55 in the last 30 days, 6 in the last 24 hours - Pilot; age 28; injuries: none; flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: helicopter, airplane; medical: class 1, without waivers/limitations; seat: right; restraint: 3-point; flight hours: 897 total, 57 in this make and model ## Weather - Conditions: Visual (VMC), Night - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 39 °F, dew point 18 °F - Altimeter: 30.42 inHg - Observed at: KRDM ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20130117000459A](https://openairdocs.org/incident/20130117000459A), Jan 17, 2013: Cessna 172RG, Redmond, OR, Substantial damage. The left main gear leg failed to fully extend to a down & locked position when gear was lowered after several successful touch & go's at bend (S07). Pilot… ## Docket (9 files) The files NTSB released with the investigation on March 21, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=86082. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40407449&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Photo 1 - Damage to Lower Fuselage (item 2, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40407456&FileExtension=.PDF&FileName=Photo%201%20-%20Damage%20to%20Lower%20Fuselage-Master.PDF - Cessna Materials and Process Laboratory Report (item 3, .PDF, 1.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40407450&FileExtension=.PDF&FileName=Cessna%20Materials%20and%20Process%20Laboratory%20Report-Master.PDF - Maintenance Logbook Excerpts (item 4, .PDF, 2.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40407451&FileExtension=.PDF&FileName=Maintenance%20Logbook%20Excerpts-Redacted.PDF - Statement of Party Representatives to NTSB Investigation (item 5, .PDF, 232 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40407452&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.PDF - Cessna Service Bulletin SEB90-1 Revision 3 (item 6, .PDF, 994 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40407453&FileExtension=.PDF&FileName=Cessna%20Service%20Bulletin%20SEB90-1%20Revision%203-Master.PDF - FAA Airworthiness Directive AD 2001-06-06 (item 7, .PDF, 51 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40407455&FileExtension=.PDF&FileName=FAA%20Airworthiness%20Directive%20AD%202001-06-06-Master.PDF - Evidence Control Form (item 8, .PDF, 268 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40407527&FileExtension=.PDF&FileName=Evidence%20Control%20Form-Master.PDF - Cessna Permission to Include Materials and Process Report in the Docket (item 9, .PDF): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40410677&FileExtension=.PDF&FileName=Cessna%20Permission%20to%20Include%20Materials%20and%20Process%20Report%20in%20the%20Docket%20%20-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.