OpenAirDocs.org

Sloped/uneven terrain

Open the Markdown

NTSB finding · Environmental issues › Physical environment › Terrain

All 270 cases102 in the probable cause
Cases
270
In the probable cause
102 (38%)
Fatal cases
13
NTSB code
03021017

NTSB has coded findings and defining events since 2008. Earlier cases used its older occurrence and cause codes, so they aren’t counted here.

When and where

In green, cases where NTSB made it part of the probable cause; in gray, a factor or other finding. Findings are coded with the final report, often a year or more after the event, so the latest years are incomplete.

Cases per year

2008In the probable causeFactor only2026

Where

Open the map
Query with SQL
duckdb -csv -c "SELECT year(c.\"eventDate\") AS year, count(DISTINCT f.case_mkey) AS cases,
    count(DISTINCT f.case_mkey) FILTER (WHERE f.\"inProbableCause\") AS in_probable_cause
  FROM 'https://openairdocs.org/data/latest/ntsb_findings.parquet' f JOIN 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c ON c.\"mKey\" = f.case_mkey
  WHERE starts_with(f.\"findingCode\", '03021017') AND c.\"eventDate\" >= DATE '2000-01-01'
  GROUP BY 1
  ORDER BY 1"

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

In the same cases

Defining events
Aircraft models

Aircraft matched to the registry by N-number and date.

Other findings
Query with SQL
duckdb -csv -c "WITH matched AS (SELECT DISTINCT case_mkey, aircrafts_position FROM 'https://openairdocs.org/data/latest/ntsb_findings.parquet' WHERE starts_with(\"findingCode\", '03021017'))
  SELECT * FROM (
  SELECT 'Defining event' AS kind, e.\"tier2Number\" AS code, max(e.\"eventTier2Name\") AS name, count(DISTINCT f.case_mkey) AS cases
  FROM matched f JOIN 'https://openairdocs.org/data/latest/ntsb_events.parquet' e ON e.case_mkey = f.case_mkey AND e.aircrafts_position = f.aircrafts_position AND e.\"isDefiningEvent\"
  WHERE e.\"tier2Number\" <> ''
  GROUP BY ALL
  UNION ALL
  SELECT 'Aircraft model', a.aircraft_model_code, any_value(concat_ws(' ', m.manufacturer, m.model)), count(DISTINCT f.case_mkey)
  FROM matched f JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = f.case_mkey AND a.position = f.aircrafts_position
  LEFT JOIN 'https://openairdocs.org/data/latest/faa_aircraft_model.parquet' m ON m.code = a.aircraft_model_code
  WHERE a.aircraft_model_code IS NOT NULL
  GROUP BY ALL
  UNION ALL
  SELECT 'Other finding', left(g.\"findingCode\", 8), max(g.\"tier4Name\"), count(DISTINCT g.case_mkey)
  FROM 'https://openairdocs.org/data/latest/ntsb_findings.parquet' g
  WHERE g.case_mkey IN (SELECT case_mkey FROM matched) AND NOT starts_with(g.\"findingCode\", '03021017') AND g.\"findingCode\" GLOB '[0-9][0-9]*'
  GROUP BY ALL
  )
  QUALIFY row_number() OVER (PARTITION BY kind ORDER BY cases DESC) <= 10
  ORDER BY kind, cases DESC"

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

Newest cases · 270

NTSB CEN26LA233Accident · No injuriesClass 4 · LimitedFinal reportBurkhart Grob Flugzeugbau G103 Twin Astir · Gregory, MIThe flight instructor’s improper planning during the simulated aborted launch which resulted in a touchdown on unsuitable terrain.Jun 3, 2026 · N4101M · Substantial damageNTSB ERA26LA199Accident · No injuriesClass 4 · LimitedFinal reportAlexander Schleicher ASW 27-18 · Greenwood, SCThe glider pilot’s encounter with a strong sink/loss of lift, which resulted in a forced landing to unsuitable terrain.Apr 20, 2026 · N27CU · Substantial damageNTSB WPR26LA146Accident · No injuriesClass 4 · LimitedFinal reportBell Helicopter Textron 206L-1 · Chimney Rock, MTThe pilot’s failure to maintain adequate clearance from the terrain while performing a low altitude circling takeoff maneuver, which resulted in a dynamic rollover.Apr 4, 2026 · N5017G · Substantial damageNTSB WPR26LA087Accident · Serious injuriesClass 4 · LimitedFinal reportKitfox Series 7 · Lemmon Valley-Golden Valley, NVThe pilot’s inability to maintain clearance from terrain during a go-around.Jan 19, 2026 · N775DZ · Substantial damageNTSB WPR26LA018Accident · Minor injuriesClass 4 · LimitedFinal reportCessna 180 · Imnaha, ORThe pilot’s continued application of brakes during an aborted takeoff in a tailwind on down-sloping terrain, which resulted in a nose-over.Oct 9, 2025 · N249MD · Substantial damageNTSB WPR26LA014Accident · No injuriesClass 4 · LimitedFinal reportMaye James A Just Aircraft Escapade · Flanigan, NVThe pilot’s improper landing flare, which resulted in a hard landing.Oct 4, 2025 · N80JM · Substantial damageNTSB ANC25LA102Accident · No injuriesClass 4 · LimitedFinal reportAmerican Champion 8GCBC · Unalakleet, AKThe pilots encounter with an obstructed dip in the landing surface during the landing roll out on a remote airstrip, which resulted in a noseover.Sep 5, 2025 · N242BC · Substantial damageNTSB ANC25LA092Accident · No injuriesClass 4 · LimitedFinal reportEurocopter AS 350 B2 · Juneau, AKThe pilot’s failure to maintain adequate obstacle clearance during takeoff from uneven, snow-covered terrain in flat light conditions.Aug 22, 2025 · N149TH · Substantial damageNTSB WPR25LA226Accident · No injuriesClass 4 · LimitedFinal reportCessna 182L · Tucson Estates, AZThe pilot’s inability to stop the airplane on the runway during a rejected takeoff for undetermined reasons, which resulted in the airplane’s impact with a ditch.Jul 27, 2025 · N42725 · DestroyedNTSB ANC25LA074Accident · No injuriesClass 4 · LimitedFinal reportDehavilland Beaver DHC-2 MK.1 · Nelson Lagoon, AKThe pilot’s failure to maintain clearance from a creek bank while maneuvering to land.Jul 11, 2025 · N109KS · Substantial damage
See all 270 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.\"mKey\" IN (SELECT f.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_findings.parquet' f WHERE starts_with(f.\"findingCode\", '03021017'))
  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.