# NTSB investigations: Allison 250-C20 series: Low altitude operation/event

NTSB aviation accident and incident investigations since 1962: the probable cause, findings, aircraft, crew, weather and docket of each, linked to the FAA registry and the FAA’s own reports.

## Latest cases

- [NTSB CEN23LA279](https://openairdocs.org/ntsb/CEN23LA279.md): Bell 206B · Chapman, KS · Accident · No injuries · Class 4 · Limited · Final report · Jul 5, 2023 · N67FA · Substantial damage
  > The pilot’s failure to maintain clearance from the power line during an agricultural application pass.
- [NTSB ERA22LA206](https://openairdocs.org/ntsb/ERA22LA206.md): Bell 206 · Lake Apopka, FL · Accident · Minor injuries · Class 4 · Limited · Final report · Apr 26, 2022 · N206BX · Substantial damage
  > A collision with water following a loss of visual reference to the water surface due to sun glare.
- [NTSB CEN21LA356](https://openairdocs.org/ntsb/CEN21LA356.md): Bell 206 · Corydon, IN · Accident · Serious injuries · Class 4 · Limited · Final report · Aug 4, 2021 · N59552 · Substantial damage
  > The pilot’s failure to see and avoid power lines.
- [NTSB ERA21LA269](https://openairdocs.org/ntsb/ERA21LA269.md): Garlick Helicopters OH-58A+ · Alpine, AL · Accident · 1 fatal · Class 3 · Limited · Final report · Jun 25, 2021 · N372NS · Substantial damage
  > The pilot’s failure to maintain clearance from powerlines during a low-level aerial application flight, resulting in main rotor blade impact with a fiber-optic cable, a loss of control, and the helicopter’s subsequent impact with terrain.
- [NTSB ERA21LA262](https://openairdocs.org/ntsb/ERA21LA262.md): Mcdonnell Douglas Helicopter 369E · Swan Lake, NY · Accident · Serious injuries · Class 3 · Limited · Final report · Jun 18, 2021 · N371EE · Substantial damage
  > The pilot's failure to maintain adequate clearance from the power transmission tower structure during powerline maintenance work, which resulted in the helicopter's main rotor striking the lifeline support bracket for the tower catwalk and the subsequent loss…
- [NTSB CEN19FA020](https://openairdocs.org/ntsb/CEN19FA020.md): Hughes 369 · McDougal, AR · Accident · 1 fatal · Class 2 · Field · Final report · Nov 2, 2018 · N5187S · Destroyed
  > The pilot's failure to maintain the helicopter's clearance from the powerline structure while hovering in gusty wind conditions, which resulted in an inadvertent collision with the structure and an uncontrolled descent into terrain.
- [NTSB CEN17LA314](https://openairdocs.org/ntsb/CEN17LA314.md): Hughes 369D · Villa Grove, CO · Accident · Serious injuries · Limited investigation · Final report · Aug 10, 2017 · N58424 · Substantial damage
  > The pilot’s failure to maintain main rotor clearance from a power line tower during low-level maneuvering.
- [NTSB GAA17CA402](https://openairdocs.org/ntsb/GAA17CA402.md): Bell 206 · Uniontown, KY · Accident · No injuries · Data collection · Final report · Jun 30, 2017 · N60KH · Substantial damage
  > The pilot's failure to maintain adequate separation from power lines, which resulted in a loss of helicopter control.
- [NTSB ERA15CA055](https://openairdocs.org/ntsb/ERA15CA055.md): Mcdonnell Douglas Helicopter MD500 · Decatur, AL · Accident · No injuries · Data collection · Final report · Nov 18, 2014 · N8371F · Substantial damage
  > An undetermined pilot's failure to maintain clearance from an electrical transmission tower resulting in substantial damage to a main rotor blade. Postaccident investigation could not determine which of two pilots was flying the helicopter at the time the…
- [NTSB WPR13LA358](https://openairdocs.org/ntsb/WPR13LA358.md): Bell 206B · Chualar, CA · Accident · Minor injuries · Limited investigation · Final report · Aug 4, 2013 · N90146 · Substantial damage
  > Maintenance personnel's failure to properly tighten the bolts securing the main driveshaft to the transmission, which resulted in fatigue failure of the bolts and disconnection of the driveshaft during low-altitude flight.
- [NTSB WPR13GA128](https://openairdocs.org/ntsb/WPR13GA128.md): Bell 206B · Eureka, NV · Accident · 1 fatal · Final report · Feb 18, 2013 · N20620 · Substantial damage
  > The pilot’s failure to maintain clearance from a wire while maneuvering during low-altitude operations. Contributing to the accident was task- and/or work-related fatigue.
- [NTSB CEN12CA319](https://openairdocs.org/ntsb/CEN12CA319.md): Hughes 369HS · Delavan, MN · Accident · Serious injuries · Data collection · Final report · May 25, 2012 · N11ZX · Substantial damage
  > The pilot’s failure to maintain clearance with power lines during an aerial application flight.
- [NTSB CEN11CA533](https://openairdocs.org/ntsb/CEN11CA533.md): Garlick Helicopters OH-58C · Rushford, MN · Accident · No injuries · Data collection · Final report · Jul 31, 2011 · N82855 · Substantial damage
  > The pilot's diverted attention, which resulted in the failure to maintain clearance from the power line.
- [NTSB CEN11CA509](https://openairdocs.org/ntsb/CEN11CA509.md): Bell 206B · Temple, OK · Accident · No injuries · Data collection · Final report · Jul 23, 2011 · N118TV · Substantial damage
  > The pilot’s failure to maintain clearance from static power lines.

## The whole list in SQL

Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS:

```sql
SELECT c."ntsbNumber", c."eventDate", c."eventType", c."eventCity", c."eventStateOrRegion", a.n_number, a."aircraftMake", a."aircraftModel", c."highestInjuryLevel", c."totalFatal", c."completionStatus", c.report_url
FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = c."mKey" AND a.position = 1
WHERE c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('03020')
    AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_events.parquet' e WHERE e.case_mkey = x.case_mkey AND e.aircrafts_position = x.position AND e."isDefiningEvent" AND e."tier2Number" = '220'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb-events/220/cases?engine=03020

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