# NTSB CEN15LA309: Cessna 172RG, N6511V, Anoka, MN, July 17, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 17, 2015, 15:45 local (20:45 UTC) - Place: Anoka, MN - Coordinates: 45.141387, -93.209999 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=45.1414&lon=-93.2100&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report November 28, 2016 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA - NTSB case key (mKey): 91591 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN15LA309 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/91591/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=91591 - Page: https://openairdocs.org/ntsb/CEN15LA309 ## Probable cause Failure of the left landing gear actuator for reasons that could not be determined because the actuator was not made available for examination. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: gear extension and retract sys](https://openairdocs.org/ntsb-findings/01023230): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Cessna 172RG, 10 cases](https://openairdocs.org/ntsb-findings/01023230/cases.md?model=2072438), [All aircraft, 416 cases](https://openairdocs.org/ntsb-findings/01023230/cases.md) - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Cessna 172RG, 5 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=2072438), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: 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-flare/touchdown: 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) ## Analysis The flight instructor and commercial-rated pilot receiving instruction departed the airport. When the commercial pilot retracted the landing gear, the pilots both heard a loud "clang" from the vicinity of the left main landing gear. The pilots lowered the landing gear; the right main gear extended but the left main gear did not extend. The pilots recycled the landing gear and then attempted the emergency gear extension procedure, which were both unsuccessful in lowering the left main gear. The pilots flew to the airport and the tower controller reported that the gear was partially extended. The instructor then attempted several maneuvers to get the gear to go down and lock, but these had no effect. When the pilots determined that they would not be able to lower the left main landing gear, the flight instructor performed an intentional gear-up landing. A postaccident examination of the airplane revealed a fractured left main landing gear actuator. Numerous attempts to obtain the broken actuator from the operator were unsuccessful, and a detailed examination of the actuator was not possible. ## Factual narrative On July 17, 2015, about 1545 central daylight time, a Cessna 172RG airplane, N6511V, was substantially damaged when it landed gear up at the Anoka County-Blaine Airport (KANE), Minneapolis, Minnesota. The flight instructor and the commercial pilot receiving instruction were not injured. The airplane was registered to Kilo Delta LLC and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as an instructional flight. The flight originated from KANA about 1500.According to the pilot after conducting a landing at another airport, they taxied and departed. On departure, when the commercial pilot retracted the landing gear, they heard a loud "clang" sound from the vicinity of the left main landing gear. They lowered the landing gear and were unable to get the left main landing gear to extend. Using the normal and emergency extension procedures, they were still unable to get the left main landing gear to extend. They decided to land gear up at KANE. An examination of the airplane found damage to the bulkhead and a fractured left landing gear actuator. Numerous attempts to obtain the broken actuator from the operator were unsuccessful and a detailed examination of the actuator was not possible. ## Aircraft - Registration: [N6511V](https://openairdocs.org/aircraft/N6511V), registered now, S/N 172RG0741, 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: 172RG0741 - Year built: 1980 - Airframe hours: 7887 - Engines: LYCOMING O-360-F1A6 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, October 10, 2014, 122 hours before - Departed: ANE, MINNEAPOLIS, MN - Destination: ANE, MINNEAPOLIS, MN - Airport: ANE, Anoka County-Blaine Arpt(Janes, runway 36, 4,855 × 100 ft, asphalt - Equipment: Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 61; injuries: none; commercial, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review June 12, 2015; seat: right; restraint: 3-point; flight hours: 1,878 total, 126 in this make and model, 1,696 as pilot in command, 103 in the last 90 days, 49 in the last 30 days, 1 in the last 24 hours - Pilot; age 25; injuries: none; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; seat: left; restraint: 3-point; flight hours: 301 total, 27 in this make and model, 262 as pilot in command, 36 in the last 90 days, 8 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 320° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 84 °F, dew point 70 °F - Altimeter: 29.73 inHg - Observed at: KANE, 1 nm away ## 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 20150717010629A](https://openairdocs.org/incident/20150717010629A), Jul 17, 2015: Cessna 172RG, Blaine, MN, Substantial damage. While conducting an instructional flight, during the takeoff climb out from an outlying airport (oeo), a loud noise was noted when the gear was retracted. The… ## Docket (3 files) The files NTSB released with the investigation on September 15, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=91591. 1.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 604 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40444424&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Pilot's Statement (item 2, .PDF, 604 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40444425&FileExtension=.PDF&FileName=Pilot%27s%20Statement-Master.PDF - Photos (item 3, .PDF, 2 photos, 391 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40444426&FileExtension=.PDF&FileName=Photos-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.