# NTSB ERA16LA073: Cessna 310, N7675Q, Kennesaw, GA, December 13, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: December 13, 2015, 16:33 local (21:33 UTC) - Place: Kennesaw, GA - Coordinates: 34.013053, -84.597503 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=34.0131&lon=-84.5975&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report March 14, 2016 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA, ATL FSDO - NTSB case key (mKey): 92468 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA16LA073 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/92468/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=92468 - Page: https://openairdocs.org/ntsb/ERA16LA073 ## Probable cause Inadequate inspection and rigging of the landing gear system, which resulted in the subsequent failure and collapse of the left main landing gear during landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Maintenance: scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Cessna 310Q, 2 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md?model=2074242), [All aircraft, 320 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md) - [Landing gear system: main landing gear attach sec](https://openairdocs.org/ntsb-findings/01023211): Aircraft › Aircraft systems · Incorrect service/maintenance (probable cause); cases with it: [Cessna 310Q, 2 cases](https://openairdocs.org/ntsb-findings/01023211/cases.md?model=2074242), [All aircraft, 66 cases](https://openairdocs.org/ntsb-findings/01023211/cases.md) - [Landing gear system: main landing gear attach sec](https://openairdocs.org/ntsb-findings/01023211): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Cessna 310Q, 2 cases](https://openairdocs.org/ntsb-findings/01023211/cases.md?model=2074242), [All aircraft, 66 cases](https://openairdocs.org/ntsb-findings/01023211/cases.md) - [Inspection: scheduled/routine inspection](https://openairdocs.org/ntsb-findings/02061520): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Cessna 310Q, 1 case](https://openairdocs.org/ntsb-findings/02061520/cases.md?model=2074242), [All aircraft, 167 cases](https://openairdocs.org/ntsb-findings/02061520/cases.md) - [Maintenance/inspections: scheduled maint checks](https://openairdocs.org/ntsb-findings/01010520): Aircraft › Aircraft handling/service · Inadequate inspection (probable cause); cases with it: [Cessna 310Q, 1 case](https://openairdocs.org/ntsb-findings/01010520/cases.md?model=2074242), [All aircraft, 76 cases](https://openairdocs.org/ntsb-findings/01010520/cases.md) - [Maintenance/inspections: scheduled maint checks](https://openairdocs.org/ntsb-findings/01010520): Aircraft › Aircraft handling/service · Incorrect service/maintenance (probable cause); cases with it: [Cessna 310Q, 1 case](https://openairdocs.org/ntsb-findings/01010520/cases.md?model=2074242), [All aircraft, 76 cases](https://openairdocs.org/ntsb-findings/01010520/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Prior to flight: Aircraft maintenance event](https://openairdocs.org/ntsb-events/040); cases with it: [Cessna 310Q, 4 cases](https://openairdocs.org/ntsb-events/040/sequence.md?model=2074242), [All aircraft, 484 cases](https://openairdocs.org/ntsb-events/040/sequence.md) - [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094) (defining event); cases with it: [Cessna 310Q, 3 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=2074242), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis The private pilot was landing the airplane after conducting a local flight. He reported that, during the landing roll, after a normal touchdown on the concrete runway, the left main landing gear (MLG) collapsed. The airplane then veered left off of the runway onto grass. The airplane sustained substantial damage to the left wing, left horizontal stabilizer, and the bottom fuselage near the tail section. Examination of the airplane revealed that the left MLG down-lock bellcrank was fractured and had separated from its trunnion. The bellcrank bolt was sheared at the bolt head, consistent with overload. The upper end of the bellcrank remained attached to the outboard push-pull tube. The lower end of the bellcrank that attached to the rod end fitting at the lower side link was broken, consistent with a ductile tension failure. The fracture location was consistent with additional stress that would have been placed on the bellcrank if the landing gear had not been properly rigged. However, the damage to the landing gear precluded the ability to functionally check the gear or verify whether the landing gear system was properly rigged. According to the airplane service manual, during each annual inspection, the landing gear's down-lock tension is to be checked. Review of the airplane's maintenance logbooks revealed that the last annual inspection was completed 1 year before the accident and that the airplane had been operated for 16 hours since that inspection. The maintenance logbook entries did not indicate that the landing gear system was checked during the inspection. ## Factual narrative On December 13, 2015, about 1633 eastern standard time, a Cessna 310Q, N7675Q, operated by a private individual, was substantially damaged following a collapse of the left landing gear during landing roll at Cobb County Airport-McCollum Field, Kennesaw, Georgia. The private pilot and a passenger were not injured. Visual meteorological conditions prevailed and no flight plan was filed for the local flight. The personal flight was operated under the provisions of Title 14 Code of Federal Regulations Part 91. According to the pilot, he was cleared to land on runway 27, a 6,200 foot-long, by 100 foot-wide, concrete runway. He lowered the landing gear on downwind leg and observed three green indicator lights. After touchdown and during the landing rollout, the gear warning light illuminated and horn activated twice. The airplane continued to decelerate and was three quarters the way down runway 27, at a speed of around 35 knots, when the left landing gear collapsed. It then swerved to the left, departed the runway, and came to rest in the grass adjacent to the runway. The airplane sustained damage to the left wing, left horizontal stabilizer, and the bottom of the fuselage near the tail section, left elevator, and left aileron was bent. Examination of the airplane by an Federal Aviation Administration inspector revealed that the left main landing gear down lock bellcrank was fractured and had separated from its respective trunnion. The bellcrank bolt was sheared at the bolt head consistent with overload. The trunnion forward attach point for the bellcrank was broken and not recovered. The upper end of the bellcrank remained attached to the outboard push-pull tube. The lower end of the bellcrank, which attached to the rod end fitting at the lower side link was broken consistent with a ductile tension failure. Damage to the landing gear precluded the ability to functionally check or verify the landing gear system rigging. According to a representative from Cessna, the fracture location would be consistent with the additional stresses that would have been placed on the bellcrank with the landing gear having not been properly rigged. During an annual inspection, the down lock tension check is to be performed to verify the landing gear is adjusted correctly and locks in the down position. Review of maintenance records revealed that the airplane had been operated for about 16 hours since its most recent annual inspection, which was performed on December 1, 2014. The maintenance log book records do not reflect that the landing gear system was checked. ## Aircraft - Registration: [N7675Q](https://openairdocs.org/deregistered/N7675Q-2018-03-30), registration cancelled 2018-03-30, S/N 310Q0454, built 1972 (OpenAirDocs) - Reported make and model: CESSNA 310 (Q) - Registry model: [Cessna 310Q](https://openairdocs.org/model/cessna-310q) (registry code 2074242) (OpenAirDocs) - Registry engine: [Continental I0-470 series](https://openairdocs.org/engine/continental-i0-470-series) (registry code 17027, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 310Q0454 - Year built: 1972 - Airframe hours: 4700 - Engines: CONT MOTOR IO-470 SERIES 260 horsepower reciprocating; CONT MOTOR IO-470 SERIES 260 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, December 1, 2014, 16 hours before - Departed: RYY, Kennesaw, GA - Destination: RYY, Kennesaw, GA - Airport: RYY, Cobb County-Mc Collum Field, runway 27, 6,200 × 100 ft, asphalt - Equipment: Auto-pilot ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 69; injuries: none; private; airplane ratings: multi-engine land; medical: class 3, with waivers/limitations; last flight review January 10, 2015; seat: left; restraint: lap only; flight hours: 1,485 total, 153 in this make and model, 1,372 as pilot in command, 6 in the last 90 days, 4 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 140° at 10 knots, gusting 14 - Visibility: 10 statute miles - Temperature: 70 °F, dew point 57 °F - Altimeter: 30.03 inHg - Observed at: KRYY ## Docket (6 files) The files NTSB released with the investigation on January 29, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=92468. 2.8 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 692 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436238&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - FAA Inspector's Statement (item 2, .PDF, 44 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436239&FileExtension=.PDF&FileName=FAA%20Inspector%27s%20Statement-Master.PDF - Maintenance Records (item 3, .PDF, 993 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436240&FileExtension=.PDF&FileName=Maintenance%20Records-Master.PDF - Mainteannce Manual Reference (item 4, .PDF, 750 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436241&FileExtension=.PDF&FileName=Mainteannce%20Manual%20Reference-Master.PDF - Pilot's Statement (item 5, .PDF, 52 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436242&FileExtension=.PDF&FileName=Pilot%27s%20Statement-Master.PDF - Photo Array (item 6, .PDF, 306 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436243&FileExtension=.PDF&FileName=Photo%20Array-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.