# NTSB WPR11CA157: Aeronca 7EC, N2349E, Big Bear City, CA, March 11, 2011 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: March 10, 2011, 18:00 local (Mar 11, 2011, 02:00 UTC) - Place: Big Bear City, CA - Coordinates: 34.263889, -116.856109 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=34.2639&lon=-116.8561&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report June 8, 2011 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 78525 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR11CA157 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/78525/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=78525 - Page: https://openairdocs.org/ntsb/WPR11CA157 ## Probable cause The pilot's improper maintenance, which resulted in a wheel separating from the airplane during takeoff, and the airplane's subsequent nose over during the landing rollout. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Maintenance: installation](https://openairdocs.org/ntsb-findings/02062035): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Aeronca 7EC, 1 case](https://openairdocs.org/ntsb-findings/02062035/cases.md?model=2110120), [All aircraft, 371 cases](https://openairdocs.org/ntsb-findings/02062035/cases.md) - [Maintenance/inspections](https://openairdocs.org/ntsb-findings/01010500): Aircraft › Aircraft handling/service · Incorrect service/maintenance (probable cause); cases with it: [Aeronca 7EC, 2 cases](https://openairdocs.org/ntsb-findings/01010500/cases.md?model=2110120), [All aircraft, 103 cases](https://openairdocs.org/ntsb-findings/01010500/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: [Aeronca 7EC, 1 case](https://openairdocs.org/ntsb-events/040/sequence.md?model=2110120), [All aircraft, 484 cases](https://openairdocs.org/ntsb-events/040/sequence.md) - [Takeoff: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338) (defining event); cases with it: [Aeronca 7EC, 1 case](https://openairdocs.org/ntsb-events/338/sequence.md?model=2110120), [All aircraft, 563 cases](https://openairdocs.org/ntsb-events/338/sequence.md) - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Aeronca 7EC, 1 case](https://openairdocs.org/ntsb-events/096/sequence.md?model=2110120), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis The pilot reported that prior to takeoff, he removed the left main landing gear wheel because its tire had a slow air leak. The pilot, who held a Federal Aviation Administration issued airframe and powerplant mechanic certificate, replaced the tube and reinstalled the wheel. He indicated that when performing this maintenance, he did not properly secure the wheel’s retaining nut with a cotter pin. During the takeoff roll, the attachment nut unscrewed and the wheel separated from the axle and airplane. The pilot flew around the area for about 30 minutes in an effort to burn off fuel. Upon landing, the airplane veered left off the runway and nosed over, breaking wing ribs and a lift strut. ## Factual narrative The pilot reported that prior to takeoff, he removed the left main landing gear wheel because its tire had a slow air leak. The pilot, who holds an airframe and powerplant mechanic certificate, reported that after replacing the tube he reinstalled the wheel on his airplane. He indicated that when performing this maintenance, he did not properly secure the wheel’s retaining nut with a cotter pin. During his subsequent takeoff roll, the attachment nut unscrewed, and the wheel separated from the axle and airplane. The pilot flew around the area for about 30 minutes burning off fuel. Upon landing, the airplane veered left off the runway and nosed over, breaking wing ribs and a lift strut. ## Aircraft - Registration: [N2349E](https://openairdocs.org/aircraft/N2349E), registered now, S/N 7AC-5926, built 1946 (OpenAirDocs) - Reported make and model: AERONCA 7EC - Registry model: [Aeronca 7EC](https://openairdocs.org/model/aeronca-7ec) (registry code 2110120) (OpenAirDocs) - Registry engine: [Continental C90 series](https://openairdocs.org/engine/continental-c90-series) (registry code 17009, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 7AC-5926 - Airframe hours: 7900 - Engines: CONT MOTOR C90-12F 90 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 6, 2010, 50 hours before - Departed: L35, Big Bear City, CA - Destination: L35, Big Bear City, CA - Airport: L35, Big Bear City, runway 08, 5,850 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: none; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, without waivers/limitations; last flight review October 10, 2010; seat: front; flight hours: 4,200 total, 50 in this make and model, 4,200 as pilot in command, 14 in the last 90 days, 1 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 39 °F - Altimeter: 30.14 inHg ## Docket (1 files) The files NTSB released with the investigation on April 13, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=78525. 364 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 364 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40345152&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.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.