# NTSB WPR18LA014: American AA 1A, N9239L, Maricopa, AZ, October 21, 2017 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: October 21, 2017, 11:13 local (18:13 UTC) - Place: Maricopa, AZ - Coordinates: 33.052223, -112.140556 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.0522&lon=-112.1406&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) - Highest injury: Serious injuries - Injuries: 2 serious - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 96224 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR18LA014 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/96224/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=96224 - Page: https://openairdocs.org/ntsb/WPR18LA014 ## Probable cause The pilot’s failure to see and avoid unmarked power lines during the approach to land. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Object/animal/substance: wire](https://openairdocs.org/ntsb-findings/03022032): Environmental issues › Physical environment · Effect on operation (probable cause); cases with it: [American AA-1A, 1 case](https://openairdocs.org/ntsb-findings/03022032/cases.md?model=0630710), [All aircraft, 588 cases](https://openairdocs.org/ntsb-findings/03022032/cases.md) - [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [American AA-1A, 1 case](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=0630710), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) (defining event); cases with it: [American AA-1A, 1 case](https://openairdocs.org/ntsb-events/120/sequence.md?model=0630710), [All aircraft, 1,074 cases](https://openairdocs.org/ntsb-events/120/sequence.md) - [Approach: Loss of control in flight](https://openairdocs.org/ntsb-events/240); cases with it: [American AA-1A, 6 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=0630710), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Approach: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [American AA-1A, 11 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=0630710), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot was conducting a local personal flight. His son reported that his father was returning to the departure airport when the accident occurred. One witness reported that the airplane “seemed slow and too low” during the approach to land and that it struck power lines near the approach end of the runway. Subsequently, the airplane descended rapidly and impacted the runway. Several other witnesses reported that the airplane impacted unmarked power lines that were above a power line marked with orange guide balls. The pilot did not recall the accident sequence. Postaccident examination of the airplane did not reveal any preaccident mechanical malfunctions or failures that would have precluded normal operation. Given the witness statements, it is likely that, during the approach to land, the pilot allowed the airplane to drop below the glideslope, and he failed to see and avoid the unmarked power lines that were above the marked power line. ## Factual narrative On October 21, 2017, about 1113 mountain standard time, an American Aviation AA-1A airplane, N9239L, was substantially damaged when it was involved in an accident near Maricopa, Arizona. The pilot and passenger were seriously injured. The airplane was being operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot’s son reported that his father was returning to the departure airport when the accident occurred. A witness reported that the airplane “seemed slow and low” during the approach to land and that it then struck power lines. Subsequently, the airplane descended rapidly and impacted the runway, sustaining substantial damage to the right wing and fuselage. Several witnesses reported that the power lines were unmarked and were above a power line marked with orange guide balls. The pilot did not recall the accident. One of the witnesses reported seeing a power line wrapped around the landing gear. Examination of the airplane did not reveal evidence of any preaccident mechanical malfunctions or failures that would have precluded normal operation. Control continuity was established. ## Aircraft - Registration: [N9239L](https://openairdocs.org/deregistered/N9239L-2020-05-29), registration cancelled 2020-05-29, S/N AA1A-0139 (OpenAirDocs) - Reported make and model: AMERICAN AVIATION AA 1A - Registry model: [American AA-1A](https://openairdocs.org/model/american-aa-1a) (registry code 0630710) (OpenAirDocs) - Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: AA1A-0139 - Engines: Lycoming O-235 reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Departed: 2AZ4, Maricopa, AZ - Destination: 2AZ4, Maricopa, AZ - Airport: 2AZ4, Millar Airport, runway 16, 2,600 × 75 ft, asphalt - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 75; injuries: serious; private; airplane ratings: single-engine land, multi-engine land; medical: basicmed; seat: left; restraint: 3-point; flight hours: 1 total, 1 in this make and model, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 45 °F - Altimeter: 30.02 inHg - Observed at: CHD, 21 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 20171021021519A](https://openairdocs.org/incident/20171021021519A), Oct 21, 2017: American Aviation AA-1A, Maricopa, AZ, Substantial damage. PIC along with one passenger took off on runway 34 over powerlines marked with aviation marker balls. After approximately 30 minutes, PIC began approach on… ## Docket (5 files) The files NTSB released with the investigation on January 8, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=96224. 6.8 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 245 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=5902332&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf - Witness statements (item 2, PDF, 2 pages, 135 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11634529&FileExtension=pdf&FileName=ROM%20Witnesses-Rel.pdf - Record of email - FAA regarding postaccident exam (item 3, PDF, 1 page, 52 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9958578&FileExtension=pdf&FileName=ROE%20FAA%20EXAM-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 4, PDF, 1 page, 5.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9959373&FileExtension=pdf&FileName=N9239L%20NTSB%20Release%20signed_Redacted-Rel.pdf - On scene photos (item 5, PDF, 3 pages, 484 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9958475&FileExtension=pdf&FileName=On%20Scene%20Photos-Rel.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.