NTSB investigations
35,883 cases where the phase of flight was Enroute.
Cases, newest first
Query with SQL
duckdb -csv -c "WITH phase_names(main, name) AS (VALUES (100, 'Prior to flight'), (150, 'Standing'), (200, 'Pushback/towing'), (250, 'Taxi'), (300, 'Takeoff'), (350, 'Initial climb'), (400, 'Enroute'), (450, 'Maneuvering'), (500, 'Approach'), (550, 'Landing'), (600, 'Emergency descent'), (650, 'Uncontrolled descent'), (700, 'Post-impact'), (750, 'After landing'), (800, 'Other'), (990, 'Unknown')),
crosswalk(code, main, name) AS (VALUES (500, 150, 'Standing'), (501, 150, 'Standing - pre-flight'), (502, 150, 'Standing - starting engine(s)'), (503, 150, 'Standing - engine(s) operating'), (504, 150, 'Standing - engine(s) not operating'), (505, 150, 'Standing - idling rotors'), (510, 250, 'Taxi'), (511, 200, 'Taxi - pushback/tow'), (512, 250, 'Taxi - to takeoff'), (513, 250, 'Taxi - from landing'), (514, 250, 'Taxi - aerial'), (520, 300, 'Takeoff'), (521, 300, 'Takeoff - roll/run'), (522, 350, 'Takeoff - initial climb'), (523, 300, 'Takeoff - aborted'), (530, 400, 'Climb'), (531, 400, 'Climb - to cruise'), (540, 400, 'Cruise'), (541, 400, 'Cruise - normal'), (542, 400, 'Maneuvering - holding (IFR)'), (550, 400, 'Descent'), (551, 400, 'Descent - normal'), (552, 600, 'Descent - emergency'), (553, 650, 'Descent - uncontrolled'), (560, 500, 'Approach'), (561, 500, 'Approach - VFR pattern - downwind'), (562, 500, 'Approach - VFR pattern - base turn'), (563, 500, 'Approach - VFR pattern - base leg/base to final'), (564, 500, 'Approach - VFR pattern - final approach'), (565, 500, 'Go-around (VFR)'), (566, 500, 'Approach - IAF to FAF/outer marker (IFR)'), (567, 500, 'Approach - FAF/outer marker to threshold (IFR)'), (568, 500, 'Circling (IFR)'), (569, 500, 'Missed approach (IFR)'), (570, 550, 'Landing'), (571, 550, 'Landing - flare/touchdown'), (572, 550, 'Landing - roll'), (573, 550, 'Landing - aborted'), (574, 550, 'Emergency landing'), (575, 550, 'Emergency landing after takeoff'), (576, 600, 'Emergency descent/landing'), (580, 450, 'Maneuvering'), (581, 450, 'Maneuvering - aerial application'), (582, 450, 'Maneuvering - turn to reverse direction'), (583, 450, 'Maneuvering - turn to landing area (emergency)'), (590, 450, 'Hover'), (591, 450, 'Hover - in ground effect'), (592, 450, 'Hover - out of ground effect'), (600, 800, 'Other'), (610, 990, 'Unknown')),
current_codes AS (
SELECT e.case_mkey, TRY_CAST(e.\"tier1Number\" AS INTEGER) AS code,
row_number() OVER (PARTITION BY e.case_mkey ORDER BY coalesce(e.\"isDefiningEvent\", false) DESC, e.position) AS n
FROM 'https://openairdocs.org/data/latest/ntsb_events.parquet' e
WHERE e.aircrafts_position = 1 AND e.\"tier1Number\" GLOB '[1-9][0-9]*'
AND (e.\"isDefiningEvent\" OR e.case_mkey IN (SELECT \"mKey\" FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' WHERE \"isPre1982\"))
),
phases AS (
SELECT case_mkey, 'current' AS scheme, code, CASE WHEN code >= 990 THEN 990 ELSE code // 50 * 50 END AS main
FROM current_codes WHERE n = 1
UNION ALL
SELECT o.case_mkey, 'older', o.\"phaseOfFlightCode\", w.main
FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o JOIN crosswalk w ON w.code = o.\"phaseOfFlightCode\"
WHERE o.aircrafts_position = 1 AND o.\"occurrenceNumber\" = 1 AND o.case_mkey NOT IN (SELECT case_mkey FROM current_codes)
),
case_phases AS (
SELECT p.*, c.\"eventDate\", c.\"highestInjuryLevel\" = 'Fatal' AS fatal, a.aircraft_model_code
FROM phases p JOIN 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c ON c.\"mKey\" = p.case_mkey
LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = p.case_mkey AND a.position = 1
WHERE c.\"eventDate\" >= DATE '1962-01-01' AND p.main IN (SELECT main FROM phase_names)
)
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 case_mkey FROM case_phases WHERE main = 400)
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.
WITH phase_names(main, name) AS (VALUES (100, 'Prior to flight'), (150, 'Standing'), (200, 'Pushback/towing'), (250, 'Taxi'), (300, 'Takeoff'), (350, 'Initial climb'), (400, 'Enroute'), (450, 'Maneuvering'), (500, 'Approach'), (550, 'Landing'), (600, 'Emergency descent'), (650, 'Uncontrolled descent'), (700, 'Post-impact'), (750, 'After landing'), (800, 'Other'), (990, 'Unknown')),
crosswalk(code, main, name) AS (VALUES (500, 150, 'Standing'), (501, 150, 'Standing - pre-flight'), (502, 150, 'Standing - starting engine(s)'), (503, 150, 'Standing - engine(s) operating'), (504, 150, 'Standing - engine(s) not operating'), (505, 150, 'Standing - idling rotors'), (510, 250, 'Taxi'), (511, 200, 'Taxi - pushback/tow'), (512, 250, 'Taxi - to takeoff'), (513, 250, 'Taxi - from landing'), (514, 250, 'Taxi - aerial'), (520, 300, 'Takeoff'), (521, 300, 'Takeoff - roll/run'), (522, 350, 'Takeoff - initial climb'), (523, 300, 'Takeoff - aborted'), (530, 400, 'Climb'), (531, 400, 'Climb - to cruise'), (540, 400, 'Cruise'), (541, 400, 'Cruise - normal'), (542, 400, 'Maneuvering - holding (IFR)'), (550, 400, 'Descent'), (551, 400, 'Descent - normal'), (552, 600, 'Descent - emergency'), (553, 650, 'Descent - uncontrolled'), (560, 500, 'Approach'), (561, 500, 'Approach - VFR pattern - downwind'), (562, 500, 'Approach - VFR pattern - base turn'), (563, 500, 'Approach - VFR pattern - base leg/base to final'), (564, 500, 'Approach - VFR pattern - final approach'), (565, 500, 'Go-around (VFR)'), (566, 500, 'Approach - IAF to FAF/outer marker (IFR)'), (567, 500, 'Approach - FAF/outer marker to threshold (IFR)'), (568, 500, 'Circling (IFR)'), (569, 500, 'Missed approach (IFR)'), (570, 550, 'Landing'), (571, 550, 'Landing - flare/touchdown'), (572, 550, 'Landing - roll'), (573, 550, 'Landing - aborted'), (574, 550, 'Emergency landing'), (575, 550, 'Emergency landing after takeoff'), (576, 600, 'Emergency descent/landing'), (580, 450, 'Maneuvering'), (581, 450, 'Maneuvering - aerial application'), (582, 450, 'Maneuvering - turn to reverse direction'), (583, 450, 'Maneuvering - turn to landing area (emergency)'), (590, 450, 'Hover'), (591, 450, 'Hover - in ground effect'), (592, 450, 'Hover - out of ground effect'), (600, 800, 'Other'), (610, 990, 'Unknown')),
current_codes AS (
SELECT e.case_mkey, TRY_CAST(e."tier1Number" AS INTEGER) AS code,
row_number() OVER (PARTITION BY e.case_mkey ORDER BY coalesce(e."isDefiningEvent", false) DESC, e.position) AS n
FROM 'https://openairdocs.org/data/latest/ntsb_events.parquet' e
WHERE e.aircrafts_position = 1 AND e."tier1Number" GLOB '[1-9][0-9]*'
AND (e."isDefiningEvent" OR e.case_mkey IN (SELECT "mKey" FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' WHERE "isPre1982"))
),
phases AS (
SELECT case_mkey, 'current' AS scheme, code, CASE WHEN code >= 990 THEN 990 ELSE code // 50 * 50 END AS main
FROM current_codes WHERE n = 1
UNION ALL
SELECT o.case_mkey, 'older', o."phaseOfFlightCode", w.main
FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o JOIN crosswalk w ON w.code = o."phaseOfFlightCode"
WHERE o.aircrafts_position = 1 AND o."occurrenceNumber" = 1 AND o.case_mkey NOT IN (SELECT case_mkey FROM current_codes)
),
case_phases AS (
SELECT p.*, c."eventDate", c."highestInjuryLevel" = 'Fatal' AS fatal, a.aircraft_model_code
FROM phases p JOIN 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c ON c."mKey" = p.case_mkey
LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = p.case_mkey AND a.position = 1
WHERE c."eventDate" >= DATE '1962-01-01' AND p.main IN (SELECT main FROM phase_names)
)
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 case_mkey FROM case_phases WHERE main = 400)
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESCRun it at the DuckDB prompt, or in any tool that reads Parquet over HTTPS. More ways to query the release are on Use the data.
NTSB GAA18CA330Accident · No injuriesData collectionFinal reportSorensen Danny S BF9 2 · Evanston, WYThe pilot’s failure to fuel the biplane’s main fuel tank before the flight and his inadequate preflight inspection, during which he did not verify the fuel quantity, which resulted in fuel exhaustionNTSB WPR18LA156Accident · Minor injuriesLimited investigationFinal reportBeech A36 · Tonopah, NVThe pilot's failure to properly lean the fuel/air mixture and to monitor critical engine parameters during the en route climb to cruise level, which resulted in excessive engine heat and oil starvation and the subsequent catastrophic engine failure.NTSB GAA18CA312Accident · No injuriesData collectionFinal reportPiper PA 46 · Prescott, AZThe pilot’s improper fuel planning, which resulted in fuel exhaustion and the subsequent total loss of engine power.NTSB CEN18LA200Accident · No injuriesClass 3 · LimitedFinal reportIrlbeck Thomas H RV 8 · Somerset, WIA total loss of engine power due to damaged and disconnected electronic ignition wires from both the main and backup batteries, which resulted in a forced landing.NTSB WPR18LA151Accident · 1 fatalLimited investigationFinal reportCessna 150M · Bainbridge Island, WAThe pilot's failure to maintain clearance from the water and his distraction by using the tablet for navigation, which resulted in his failure to detect that the airplane had entered a descent.NTSB ERA18WA156Incident · No injuriesForeign investigationCessna 152 · Tulua, ColombiaThe government of Colombia has notified the NTSB of an accident involving a CESSNA 152 airplane that occurred on May 28, 2018. The NTSB has appointed a U.S. Accredited Representative to assist the government of Colombia's investigation under the provisions of…NTSB CEN18LA199Accident · Serious injuriesLimited investigationFinal reportAeronca 58B · Tekamah, NEThe partial loss of engine power due to the formation of carburetor ice. Contributing to the accident was the pilot's failure to use carburetor heat and his decision to continue flight with reduced engine power rather than landing the airplane on suitable…NTSB WPR18LA149Accident · No injuriesClass 3 · LimitedFinal reportCessna 182 · Aberdeen, IDThe pilot's failure to use carburetor heat while operating in conditions conducive to carburetor icing, which resulted in a partial loss of engine power and a subsequent forced landing and nose-over.NTSB GAA18CA325Accident · Minor injuriesData collectionFinal reportCosentino Garey A Pegasus · Kingston, OKThe pilot’s failure to maintain altitude and the powered parachute’s subsequent impact with trees.NTSB GAA18CA307Accident · No injuriesData collectionFinal reportPiper PA28 · Butler, KYThe pilot’s improper fuel management, which resulted in fuel starvation.NTSB ERA18LA155Accident · No injuriesClass 3 · LimitedFinal reportDevries WM H Kitfox Sport · Taghkanic, NYA total loss of engine power for reasons that could not be determined based on the available information.NTSB CEN18FA192Accident · 1 fatalField investigationFinal reportBeech D17S · Santa Fe, NMThe pilot's failure to maintain clearance from terrain for reasons that could not be determined based on the available information.NTSB WPR18LA145Accident · Minor injuriesLimited investigationFinal reportSportavia Putzer RF5B Sperber · Lookout Pass, MTThe pilot’s improper decision to continue flight toward rising terrain after the engine overheated, which necessitated a precautionary landing when the motorglider could not maintain altitude in downdrafts.NTSB ERA18FA150Accident · 1 fatalField investigationFinal reportPiper PA28 · Chesapeake, VAThe pilot's loss of airplane control due to spatial disorientation during the departure climb in instrument meteorological conditions.NTSB CEN18LA189Accident · Serious injuriesClass 3 · LimitedFinal reportM-Squared Sprint 1000 · Gurdon, ARInadequate engine maintenance, which resulted in the failure of the MAG piston ring and the subsequent total loss of engine power due to a piston seizure.NTSB ERA18FA148Accident · 1 fatalField investigationFinal reportPiper PA34 · Bennington, VTThe pilot's improper decision to attempt a visual flight rules flight in instrument meteorological conditions, which resulted in a loss of control during a turn.NTSB CEN18LA181Accident · Minor injuriesClass 3 · LimitedFinal reportVans RV7A · Hanover Park, ILA partial loss of engine power shortly after takeoff due to water contamination of the fuel system.NTSB ERA18WA151Accident · 2 fatalForeign investigationCessna 210 · Itacoatiara, BrazilThe government of Brazil has notified the NTSB of an accident involving a CESSNA 210 airplane that occurred on May 16, 2018. The NTSB has appointed a U.S. Accredited Representative to assist the government of Brazil's investigation under the provisions of…NTSB ENG18WA027Incident · No injuriesForeign investigationBombardier CL600 2B19 · Geuteng, South Africa, South AfricaThe Government of South Africa has notified the NTSB of an incident involving a Bombardier CL-600-2B19 that occurred May 16, 2018. The NTSB has appointed a U.S. Accredited Representative to assist the South African Civil Aviation Authority (CAA) investigation…NTSB CEN18LA174Accident · No injuriesLimited investigationFinal reportCessna 177 · Fort Wayne, INThe failure of the oil cooler due to a defect in the brazed joint, which resulted in a loss of engine power due to oil starvation.NTSB WPR18FA141Accident · 1 fatalField investigationFinal reportCessna 182G · Cascade, IDThe non-instrument-rated pilot's improper decision to initiate a visual flight rules flight into an area with low ceilings due to mountain obscuration, which resulted in controlled flight into terrain.NTSB GAA18CA283Accident · No injuriesData collectionFinal reportSchweizer SGS123 · Tunbridge, VTThe student glider’s inability to maintain altitude due to a loss of thermal lift, which resulted in an off-airport landing.NTSB ERA18FA146Accident · 1 fatalField investigationFinal reportBeech 35A33 · Jacksonville, ALThe pilot/mechanic's inadequate inspection of the exhaust system, including the left muffler and heat exchanger, which precluded his detection of preexisting cracks and led to a missed opportunity to replace the components. The inadequate inspection allowed…NTSB CEN18WA191Accident · 3 fatalForeign investigationMooney M20K · Tarragona, PortugalOn May 12, 2018, about 1340 coordinated universal time, a Mooney M20K airplane, D-EFTF, impacted terrain near Tarragone, Portugal, after reporting an engine issue to air traffic control. The pilot and two passengers were fatally injured. The airplane was…NTSB ANC18FA036Accident · 1 fatalClass 2 · FieldFinal reportPiper PA-28-180 · Whittier, AKThe student pilot's decision to depart and continue on a solo cross-country flight through mountainous terrain in marginal visual flight rules conditions, which resulted in controlled flight into terrain.NTSB WPR18LA142Accident · Serious injuriesLimited investigationFinal reportKolb Firestar · Atmore, ALThe noncertificated pilot's failure to maintain airplane control, which resulted in an aerodynamic stall. Contributing to the accident was the pilot's lack of flight experience and qualification.NTSB ERA18WA153Accident · 1 fatalClass 5 · ForeignBell Helicopter 206 · Barra da Tijuca, BrazilNTSB GAA18CA264Accident · No injuriesData collectionFinal reportPiper PA28 · Addison, TXThe pilot’s inadequate preflight fuel planning, which resulted in a total loss of engine power due to fuel exhaustion.NTSB DCA18WA177Incident · No injuriesForeign investigationBoeing 767 · GuayaquilThe Civil Aviation Authority of Ecuador has notified the NTSB of an incident involving a Boeing 767-300, which occurred on May 8, 2018. The NTSB has appointed a U.S Accredited Representative to assist under the provisions of ICAO Annex 13. All investigative…NTSB ERA18TA142Accident · Minor injuriesFinal reportBarry Maggio Apollo AG-1 · Smith Beach, VAThe noninstrument-rated pilot's inadequate preflight and in-flight weather planning, which resulted in an off-airport precautionary landing to avoid weather and a subsequent collision with power lines.NTSB ANC18LA034Accident · Serious injuriesClass 3 · LimitedFinal reportGrumman TBM-3 · Fort Apache, AZA partial loss of engine power for reasons that could not be determined based on the available information.NTSB GAA18CA273Accident · Minor injuriesData collectionFinal reportChristopher Lord ELA Eclipse 10 · Calhoun, GAThe student pilot’s failure to maintain sufficient airspeed, which resulted in a loss of altitude and necessitated a sudden descent to unsuitable terrain.NTSB DCA18WA174Incident · No injuriesForeign investigationBoeing 737 · Arequipa, PeruThe government of Peru has notified the NTSB of an incident involving a BOEING 737 airplane that occurred on May 05, 2018. The NTSB has appointed a U.S. Accredited Representative to assist the government of Peru's investigation under the provisions of ICAO…NTSB CEN18LA159Accident · No injuriesLimited investigationFinal reportBeech A36 · Shullsburg, WIA catastrophic engine failure due to improper torque on the engine through-bolt nuts, which resulted in relative movement between the crankcase halves, damage to a main journal bearing, and a loss of oil lubrication.NTSB WPR18LA135Accident · Serious injuriesClass 3 · LimitedFinal reportCessna 152 · Tamiami, FLThe non-instrument-rated pilot’s loss of control during an encounter with instrument meteorological conditions at night. Contributing to the accident was the pilot's decision to depart on the flight without obtaining approval to fly at night in accordance…NTSB ERA18WA166Accident · No injuriesForeign investigationPZL Swidnik SW4 · Curitibanos, BrazilThe government of Brazil has notified the NTSB of an accident involving a PZL Swidnik, SW4, helicopter that occurred on May 4, 2018. The NTSB has appointed a U.S. Accredited Representative to assist the government of Brazil's investigation under the…NTSB DCA18WA180Incident · No injuriesForeign investigationBoeing 737 · Port Elizabeth, South AfricaThe Civil Aviation Authority (CAA) of South Africa has informed the NTSB of an incident involving a Boeing 737-300, which occurred on May 4, 2018. The NTSB has appointed a U.S Accredited Representative to assist the CAA investigation under the provisions of…NTSB WPR18FA131Accident · 1 fatalField investigationFinal reportAmerican Air Racing Thunder Mustang · Reno, NVThe pilot's failure to properly secure the engine coolant pump pulley during recent maintenance, which resulted in a loss of the engine's lubrication, cooling, and propeller control systems, and a forced landing, during which the airplane nosed over.…NTSB GAA18CA347Accident · No injuriesData collectionFinal reportPiper PA28 · Pine Spring, TXThe pilot’s failure to maintain adequate altitude while flying over mountainous terrain in turbulent wind conditions at night, which resulted in a tree strike.NTSB ERA18WA139Accident · 2 fatalForeign investigationAgusta Bell AB206B · Cacao, French GuianaThe government of France has notified the NTSB of an accident involving a Agusta Bell AB206B helicopter that occurred on May 2, 2018 near Cacao, French Guiana. The NTSB has appointed a U.S. Accredited Representative to assist the government of France's…NTSB ERA18LA140Accident · Minor injuriesLimited investigationFinal reportRobinson R22 · Panama City, FLThe pilot's failure to properly remove and secure the tie-down ropes during the preflight inspection, which resulted in the ropes becoming entangled in the rotor head swashplate and pitch control rods during flight and the subsequent loss of pitch control.NTSB DCA18WA171Incident · No injuriesForeign investigationBoeing 737 · Bangkok, ThailandThe Air Accident Investigation Committee of Thailand has notified the NTSB of a serious incident involving a BOEING 737 airplane that occurred on May 02, 2018. The NTSB has appointed a U.S. Accredited Representative to assist the government of Thailand's…NTSB CEN18WA253Incident · No injuriesForeign investigationBeech 400 · Geneva, SwitzerlandOn May 2, 2018, about 1035 Universal Coordinated Time, a Beech 400, United Kingdom registration G-FXAR, experienced a cabin depressurization event and landed without further incident at the Geneva International Airport (LSGG), Geneva, Switzerland. There were…NTSB CEN18LA156Accident · No injuriesLimited investigationFinal reportLaminar Lancair 360 · Woodward, OKThe pilot-rated passenger’s inadvertent contact with and closure of the emergency fuel shutoff valve, which resulted in the total loss of engine power due to fuel starvation. Contributing to the accident was the pilot's lack of experience in the accident…NTSB ERA18FA137Accident · 1 fatalField investigationFinal reportPiper PA28R · Gainesville, GAA partial loss of engine power due to inadequate thru-bolt and stud preload tension by undetermined maintenance personnel, which resulted in fretting between the engine crankcase halves, and the subsequent separation of the No. 2 cylinder due to the fatigue…NTSB CEN18WA401Accident · No injuriesForeign investigationBeech 58 · Hautes-Alpes, FranceOn April 28, 2018, about 0720 UTC, a Beechcraft BE-58P, Swiss registry HB-GGP, operated by a private individual, experienced an uncontained engine failure while in cruise flight near the Hautes-Alpes, France. The pilot, the sole person on board was not…NTSB CEN18LA150Accident · 2 fatalLimited investigationFinal reportWolfe Kitfox V · Kalkaska, MIThe pilot's failure to maintain airplane control that resulted in a stall/spin following climb from the departure airport.NTSB CEN18FA149Accident · 3 fatalField investigationFinal reportEurocopter AS 350 B2 · Hazelhurst, WIThe pilot's loss of helicopter control as a result of fatigue during cruise flight at night.NTSB CEN18LA151Accident · Minor injuriesLimited investigationFinal reportCessna 152 · Cullman, ALThe pilot’s inadvertent engine shutdown due to excessive leaning of the engine and his subsequent inability to restart the engine.NTSB CEN18LA146Accident · Minor injuriesLimited investigationFinal reportCessna T303 · Pine Ridge, SDThe airplane’s inadvertent encounter with severe icing conditions during descent, which resulted in structural icing, the pilot’s inability to maintain altitude, and an emergency landing. Contributing to the accident was an incomplete preflight weather…