NTSB investigations: Lycoming IO-540-AE1A5, AK

12 cases on aircraft whose registry engine model is Lycoming IO-540-AE1A5. Aircraft are matched to the registry by N-number and event date, checked against the reported serial number, make and model, so older matches can be wrong.

Cases per year

20092026
NTSB investigations: Lycoming IO-540-AE1A5, AK per year, 2009–2026: 12 cases
20091
20121
20151
20161
20171
20181
20191
20211
20221
20231
20241
20251

Latest cases

Query with SQL
duckdb -csv -c "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.\"eventStateOrRegion\" = 'AK' AND c.\"eventCountry\" = 'USA'
    AND c.\"mKey\" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41899'))
  ORDER BY c.\"eventDate\" DESC, c.\"ntsbNumber\" DESC"

Prints the whole list as CSV. It reads the release’s Parquet files over HTTPS, so there’s nothing to download first. Install DuckDB to run it.

NTSB ANC25LA064Accident · No injuriesClass 4 · LimitedFinal reportRobinson Helicopter R44 II · Palmer, AKThe pilot’s diverted attention during takeoff in flat light conditions, which resulted in a loss of visual reference with terrain.Jun 30, 2025 · N531AT · Substantial damageNTSB ANC24LA079Accident · Minor injuriesClass 4 · LimitedFinal reportRobinson Helicopter R44 II · Palmer, AKThe pilot's failure to follow the operator’s procedure manual and attempted to land at a remote landing zone in high wind conditions. Contributing factor was the pilot’s decision to not conduct a fly over of the landing site to determine wind condition which…Aug 18, 2024 · N783AK · Substantial damageNTSB ANC23LA032Accident · Minor injuriesClass 4 · LimitedFinal reportRobinson Helicopter R44 II · Skwentna, AKThe pilot's failure to maintain adequate altitude/clearance from terrain while maneuvering in adverse weather conditions, which resulted in a dynamic rollover.May 9, 2023 · N704T · Substantial damageNTSB WPR22LA299Accident · Minor injuriesClass 4 · LimitedFinal reportRobinson Helicopter R44 II · Palmer, AKThe pilot’s failure to maintain lateral control during an off-field landing, which resulted in loss of control and an impact with terrain.Aug 11, 2022 · N987WH · Substantial damageNTSB ANC22LA001Accident · No injuriesClass 4 · LimitedFinal reportRobinson Helicopter R44 II · Palmer, AKThe unmanned aircraft pilot’s failure to yield the right of way to the helicopter.Oct 10, 2021 · N555EL · 2 aircraft · Substantial damageNTSB GAA19CA531Accident · No injuriesData collectionFinal reportRobinson R44 · Nuiqsut, AKThe pilot's improper decision to land downwind from unsecured debris, which resulted in the helicopter’s main rotor disk ingesting foreign objects.Sep 6, 2019 · N447PA · Substantial damageNTSB GAA18CA534Accident · No injuriesData collectionFinal reportRobinson R44 · Girdwood, AKThe fisherman's fishing rod striking the helicopter’s rotating main rotor disk during loading.Aug 30, 2018 · N99645 · Substantial damageNTSB ANC17LA040Accident · No injuriesClass 3 · LimitedFinal reportRobinson Helicopter R44 · Solomon, AKThe pilot's failure to maintain adequate altitude above water, and his loss of situational awareness, which resulted in an inadvertent descent and collision with water.Aug 3, 2017 · N4138M · Substantial damageNTSB ANC16IA013Incident · No injuriesIncident investigationFinal reportRobinson Helicopter R44 II · Anchorage, AKThe overhaul facility's improper and excessive use of an approved lubricant during overhaul of the fuel injection servo, which resulted in a disruption of fuel flow and a total loss of engine power.Jan 7, 2016 · N395CE · No damageNTSB ANC16LA010Accident · No injuriesLimited investigationFinal reportRobinson Helicopter R44 II · Valdez, AKThe overhaul facility’s improper and excessive use of an approved lubricant during overhaul of the fuel injection servo, which resulted in a disruption of fuel flow and a total loss of engine power.Dec 16, 2015 · N255VS · Substantial damageNTSB ANC12CA018Accident · No injuriesData collectionFinal reportRobinson Helicopter R44 II · Beluga, AKGround personnel's movement of cargo in windy conditions, which allowed a previously secured cargo sack to blow into the main rotor blades.Jan 21, 2012 · N4510T · Substantial damageNTSB ANC09LA098Accident · No injuriesLimited investigationFinal reportRobinson Helicopter R44 II · Central, AKThe pilot’s failure to maintain control of the helicopter after an in-flight encounter with a downdraft while landing. Contributing to the accident was the pilot’s inadequate evaluation of wind conditions.Sep 7, 2009 · N4186Y · Substantial damage