# NTSB WPR10CA398: Kirkpatrick Buzzard, N84BS, Lincoln, CA, August 4, 2010 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Data collection · Final report - Date: August 4, 2010, 12:30 local (19:30 UTC) - Place: Lincoln, CA - Coordinates: 38.913887, -121.293891 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.9139&lon=-121.2939&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Flight control sys malf/fail](https://openairdocs.org/ntsb-events/333) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report January 7, 2011 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration FSDO - NTSB case key (mKey): 76944 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR10CA398 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/76944/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=76944 - Page: https://openairdocs.org/ntsb/WPR10CA398 ## Probable cause A loss of control due to the mechanical disconnection of an aileron pushrod from its bellcrank as a result of the mechanic's failure to properly secure the pushrod attach hardware. Also causal was the pilot's inadequate preflight inspection. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Flight control system: aileron control system](https://openairdocs.org/ntsb-findings/01022710): Aircraft › Aircraft systems · Incorrect service/maintenance (probable cause); cases with it: [Kirkpatrick Mark S BUZZARD 1 MOTORGLIDE, 1 case](https://openairdocs.org/ntsb-findings/01022710/cases.md?model=05629WE), [All aircraft, 45 cases](https://openairdocs.org/ntsb-findings/01022710/cases.md) - [Maintenance: fabrication](https://openairdocs.org/ntsb-findings/02062025): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Kirkpatrick Mark S BUZZARD 1 MOTORGLIDE, 1 case](https://openairdocs.org/ntsb-findings/02062025/cases.md?model=05629WE), [All aircraft, 30 cases](https://openairdocs.org/ntsb-findings/02062025/cases.md) - [Inspection: preflight inspection](https://openairdocs.org/ntsb-findings/02061510): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Kirkpatrick Mark S BUZZARD 1 MOTORGLIDE, 1 case](https://openairdocs.org/ntsb-findings/02061510/cases.md?model=05629WE), [All aircraft, 551 cases](https://openairdocs.org/ntsb-findings/02061510/cases.md) - [Performance/control parameters](https://openairdocs.org/ntsb-findings/01062000): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible (probable cause); cases with it: [Kirkpatrick Mark S BUZZARD 1 MOTORGLIDE, 1 case](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=05629WE), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/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: [Kirkpatrick Mark S BUZZARD 1 MOTORGLIDE, 1 case](https://openairdocs.org/ntsb-events/040/sequence.md?model=05629WE), [All aircraft, 484 cases](https://openairdocs.org/ntsb-events/040/sequence.md) - [Prior to flight: Aircraft inspection event](https://openairdocs.org/ntsb-events/050); cases with it: [Kirkpatrick Mark S BUZZARD 1 MOTORGLIDE, 1 case](https://openairdocs.org/ntsb-events/050/sequence.md?model=05629WE), [All aircraft, 229 cases](https://openairdocs.org/ntsb-events/050/sequence.md) - [Initial climb: Flight control sys malf/fail](https://openairdocs.org/ntsb-events/333) (defining event); cases with it: [Kirkpatrick Mark S BUZZARD 1 MOTORGLIDE, 1 case](https://openairdocs.org/ntsb-events/333/sequence.md?model=05629WE), [All aircraft, 410 cases](https://openairdocs.org/ntsb-events/333/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Kirkpatrick Mark S BUZZARD 1 MOTORGLIDE, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=05629WE), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The single-seat aircraft was registered with the Federal Aviation Administration (FAA) as an experimental, amateur-built aircraft. A week before the accident, the aircraft was assembled by a certificated aircraft mechanic. The pilot reported that he had previously flown the aircraft one time, for about 30 minutes. During the accident flight's takeoff roll, the pilot noticed that the aircraft did not "feel right," but he opted to continue. About 250 feet above the ground the outboard right wing "started to flutter in a violent way" and in response the pilot reduced engine power and aircraft speed. He then "lost all control." The aircraft impacted the ground in a field and seriously injured the pilot. About an hour after the accident skydivers noticed the wreckage and summoned emergency services to rescue the pilot. Examination of the wreckage by an FAA inspector revealed that the bolt that was supposed to attach an aileron pushrod to the outboard aileron bellcrank was lying loose in the bottom of the wing bay; neither the nut nor the cotter pin was recovered. Examination of the opposite aileron bellcrank revealed that the corresponding bolt and nut were not secured by a cotter pin, despite provisions for one. The mechanic who assembled the aircraft stated that he did not install cotter pins in either of the two noted bolts. The pilot stated that he did not inspect the aircraft after assembly or before the flight. ## Factual narrative The student pilot/owner reported that he had about 329 total hours of flight experience, including 250 hours in single-engine airplanes, 58 hours in ultralight aircraft, and 21 hours in gliders. He stated that the accident aircraft was a modified version of the Kolb Firefly ultralight. The single-seat aircraft was registered with the Federal Aviation Administration (FAA) as an experimental amateur-built "Buzzard 1 Motorglider." A week before the accident, the aircraft was assembled by a certificated aircraft mechanic. The pilot reported that he had previously flown the aircraft one time, for about 30 minutes. During the accident flight takeoff roll, the pilot noticed that the aircraft did not "feel right," but he opted to continue. About 250 feet above the ground, the outboard right wing "started to flutter in a violent way," and in response, the pilot reduced engine power and aircraft speed. He then "lost all control." The aircraft impacted the ground in a field, and seriously injured the pilot. About 1 hour after the accident, skydivers noticed the wreckage, and summoned emergency services to rescue the pilot. Examination of the wreckage by an FAA inspector revealed that the bolt that was supposed to attach an aileron pushrod to the outboard aileron bellcrank was lying loose in the bottom of the wing bay; neither the nut nor the cotter pin was recovered. Examination of the opposite aileron bellcrank revealed that the corresponding bolt and nut were not secured by a cotter pin, despite provisions for one. The mechanic who assembled the aircraft stated that he did not install cotter pins in either of the two noted bolts. The pilot stated that he did not inspect the aircraft after assembly, or before the flight. ## Aircraft - Registration: [N84BS](https://openairdocs.org/deregistered/N84BS-2012-09-13), registration cancelled 2012-09-13, S/N 001, built 2010 (OpenAirDocs) - Reported make and model: Kirkpatrick Buzzard (1) - Registry model: [Kirkpatrick Mark S BUZZARD 1 MOTORGLIDE](https://openairdocs.org/model/kirkpatrick-mark-s-buzzard-1-motorglide) (registry code 05629WE) (OpenAirDocs) - Registry engine: [Rotax 447](https://openairdocs.org/engine/rotax-447) (registry code 55576, 2 cycle) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 001 - Airframe hours: 0 - Engines: Rotax 442 40 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, July 15, 2010, 0 hours before - Departed: LHM, Lincoln, CA - Destination: LHM, Lincoln, CA - Flight plan: Unknown - Airport: LHM, Lincoln Regional, runway 15, 6,001 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 82; injuries: serious; student; seat: single; flight hours: 329 total, 0 in this make and model ## Weather - Conditions: Visual (VMC), Day - Visibility: 10 statute miles - Lowest ceiling: none ## 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 20100804042359A](https://openairdocs.org/incident/20100804042359A), Aug 4, 2010: Kirkpatrick BUZZARD 1 M, Lincoln, CA, Substantial damage. After take off the pilot lost control and crashed into a field next to lhm airport. It was later discovered that the lt aileron push pull tube bold fell out.… ## Docket (5 files) The files NTSB released with the investigation on September 27, 2010, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=76944. 3.8 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336427&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Pilot Interview Summary (item 2, .PDF, 37 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336428&FileExtension=.PDF&FileName=Pilot%20Interview%20Summary-Redacted.PDF - FAA Conversation Record (item 3, .PDF, 34 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336429&FileExtension=.PDF&FileName=FAA%20Conversation%20Record-Master.PDF - Mechanic's Statement (item 4, .PDF, 111 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336430&FileExtension=.PDF&FileName=Mechanic%27s%20Statement-Master.PDF - Photographs (five total) (item 5, .PDF, 432 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336431&FileExtension=.PDF&FileName=Photographs%20(five%20total)-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.