# NTSB WPR17LA080: Maxcy Christopher L Stol King, N268CR, Bozeman, MT, March 22, 2017 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: March 22, 2017, 11:30 local (18:30 UTC) - Place: Bozeman, MT - Coordinates: 45.7775, -111.151947 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=45.7775&lon=-111.1519&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: 1 uninjured - Status: Completed, report November 15, 2018 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 94904 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR17LA080 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/94904/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=94904 - Page: https://openairdocs.org/ntsb/WPR17LA080 ## Probable cause The pilot's failure to maintain directional control during landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause) - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause) ## Analysis The private pilot reported that, shortly after touchdown during landing, the experimental, amateur-built tailwheel equipped airplane immediately veered to the left. The pilot corrected with right rudder and applied engine power; however, the airplane subsequently ground looped, during which the right main landing gear strut collapsed. The pilot, who was the builder of the airplane, reported that this was the second time the gear struts had bent on this airplane. Following the first event, the pilot had reinforced the landing gear strut, but he believed that the design of the main landing gear was unable to withstand the routine stresses of landing. ## Factual narrative On March 22, 2017, about 1130 mountain standard time, an experimental, amateur-built, Christopher L. Maxcy STOL King airplane, N268CR, sustained substantial damage during the landing roll at the Bozeman Yellowstone International Airport (BZN), Bozeman, MT, following a landing gear collapse. The private pilot was not injured. The airplane was registered and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the personal, local flight which departed about 1040. The pilot reported that just after touchdown, the tail-wheeled airplane immediately veered left, and he counteracted with right rudder and a little power, but was unable to maintain direction control of the airplane. The airplane subsequently ground looped and the right main landing gear collapsed, resulting in the outboard portion of the right wing striking the runway. The airplane came to rest off the east side of the runway. Near the time of the accident, the winds were reported as variable at 3 knots. The high-wing airplane was designed for short take-off and landing (STOL) performance. It's fuselage was composed of a welded steel frame with an extended conventional landing gear. Postaccident examination of the airplane by a Federal Aviation Administration inspector revealed that the right wing was bent upwards about mid-span and was substantially damaged. Additionally, the right landing gear assembly had collapsed under the airplane. The owner and builder of the airplane stated that he had experienced a previous incident where the landing gear strut was bent during a landing, and he replaced it with a heavier duty version. He further stated that the landing gear design was not strong enough due to its long length and the angles of the gear. ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-landing roll: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094) (defining event) - [Landing-landing roll: Dragged wing/rotor/float/other](https://openairdocs.org/ntsb-events/093) ## Aircraft - Registration: [N268CR](https://openairdocs.org/aircraft/N268CR), registered now, S/N 4, built 2010 (OpenAirDocs) - Reported make and model: MAXCY CHRISTOPHER L STOL KING (NO SERIES) - Registry model: [Maxcy Christopher L STOL KING](https://openairdocs.org/model/maxcy-christopher-l-stol-king) (registry code 05630MM) (OpenAirDocs) - Registry engine: [Lycoming O-320-A2B](https://openairdocs.org/engine/lycoming-o-320-a2b) (registry code 42101, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 4 - Year built: 2010 - Airframe hours: 171.29 - Engines: LYCOMING O-320-A2B 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, April 26, 2016 - Departed: BZN, Bozeman, MT - Destination: BZN, Bozeman, MT - Airport: BZN, Bozeman Yellowstone Intl, runway 21, 2,650 × 75 ft, asphalt - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; injuries: none; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review April 8, 2016; seat: front; restraint: 3-point; flight hours: 279 total, 144 in this make and model, 144 as pilot in command, 8 in the last 90 days, 3 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 54 °F, dew point 39 °F - Altimeter: 29.85 inHg - Observed at: BZN ## 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 20170322002159A](https://openairdocs.org/incident/20170322002159A), Mar 22, 2017: Maxcy Christopher L STOL KING, Bozeman, MT, Substantial damage. On landing at the Bozeman international airport in Bozeman Montana N268CR veered to the left and ground looped. On inspection of the aircraft the right main… ## Docket (3 files) The files NTSB released with the investigation on July 17, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=94904. 3.7 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40465280&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Record of Conversation (item 2, .PDF, 37 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40465281&FileExtension=.PDF&FileName=Record%20of%20Conversation-Master.PDF - Accident Picture (item 3, .PDF, 1 photo, 104 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40465282&FileExtension=.PDF&FileName=Accident%20Picture-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- From OpenAirDocs.org, an independent open copy of NTSB and FAA data. The NTSB's own report is the official record of an investigation.