# NTSB investigations: Enroute

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.

Page 261 of 718 · 35,885 cases

## Cases, newest first

- [NTSB SEA91LA205](https://openairdocs.org/ntsb/SEA91LA205.md): Cessna 182E · Boring, OR · Accident · Minor injuries · Limited investigation · Final report · Aug 10, 1991 · N2935Y · Substantial damage
  > Fuel exhaustion and improper inflight decision by the pilot in command followed by rough terrain during the forced landing. Factors contributing to the accident were a fuel system leak and the pilot's failure to refuel en route.
- [NTSB MIA91LA197](https://openairdocs.org/ntsb/MIA91LA197.md): Cessna A188B · Monticello, FL · Accident · No injuries · Limited investigation · Final report · Aug 10, 1991 · N21684 · Substantial damage
  > Loss of engine power due to undetermined reasons and the unsuitable terrain encountered during the forced landing.
- [NTSB FTW91LA146](https://openairdocs.org/ntsb/FTW91LA146.md): Cessna A188B · Patterson, LA · Accident · Serious injuries · Limited investigation · Final report · Aug 10, 1991 · N53276 · Substantial damage
  > The pilot's failure to maintain clearance with the electical power line. Factors were the bright sun and chemical residue on the windshield.
- [NTSB DEN91LA112](https://openairdocs.org/ntsb/DEN91LA112.md): Lars Avid Flyer · Colorado Spring, CO · Accident · No injuries · Limited investigation · Final report · Aug 10, 1991 · N49BP · Substantial damage
  > The pilot's delay in flaring the airplane. Factors were: (1) stuck piston rings and (2) the pilot's failure to use flaps.
- [NTSB NYC91FA097](https://openairdocs.org/ntsb/NYC91FA097.md): Piper PA-24-180 · Muncie Valley, PA · Accident · 1 fatal · Field investigation · Final report · Aug 9, 1991 · N5007P · Destroyed
  > The pilot's attempt to maintain visual flight into known instrument meteorological conditions, resulting in a collision with trees. Factors related to the accident were: the pilot's failure to obtain a pre-flight weather briefing and his failure to maintain…
- [NTSB CHI91DER13](https://openairdocs.org/ntsb/CHI91DER13.md): Bell 47G-3B-1 · Maple Grove, MN · Accident · No injuries · Final report · Aug 9, 1991 · N73998 · Substantial damage
  > The pilot's failure to maintain directional control of the helicopter during the forced landing. Related factors are the loss of engine power, loss of rotor RPM, the eroded compressor blades, the pilot's operation with known deficiencies in equipment and…
- [NTSB ATL91FA155](https://openairdocs.org/ntsb/ATL91FA155.md): Piper PA-46-310P · Cartersville, GA · Accident · No injuries · Field investigation · Final report · Aug 7, 1991 · N9094Z · Substantial damage
  > The mechanic's improper replacement of the fuel line b-nut, and the inadequate inspection of the repair work by the quality assurance inspector.
- [NTSB LAX91LA347](https://openairdocs.org/ntsb/LAX91LA347.md): Experimental RV4 · Napa, CA · Accident · No injuries · Limited investigation · Final report · Aug 5, 1991 · N835B · Substantial damage
  > The installation of a non compatiable oil filter and system plumbing changes which induced the oil exhaustion event resulting in a forced landing and in flight collision with terrain.
- [NTSB NYC91FA199](https://openairdocs.org/ntsb/NYC91FA199.md): Beech C23 · Pleasantville, NJ · Accident · 3 fatal · Field investigation · Final report · Aug 4, 1991 · N9375S · Destroyed
  > A power loss due to a failed crankshaft, while operating over unsuitable terrain. Factors related to the accident were, the night conditions, the failure of maintenance personnel to detect the cracks using magnaflux inspections, the lack of adequate…
- [NTSB MIA91LA193](https://openairdocs.org/ntsb/MIA91LA193.md): Aero Commander 500-698 · Atlantic Ocean (Atlantic Ocean) · Accident · Serious injuries · Limited investigation · Final report · Aug 4, 1991 · N3840C · Destroyed
  > An inflight loss of power of both engines for undetermined reasons followed by a ditching in the Ocean.
- [NTSB CHI91LA244](https://openairdocs.org/ntsb/CHI91LA244.md): Aerostar Raven 557A · Indianola, IA · Accident · No injuries · Limited investigation · Final report · Aug 4, 1991 · N3621X · Substantial damage
  > Failure of the pilot to maintain altitude. Factors associated with the accident are complacency and diverted attention.
- [NTSB LAX91LA343](https://openairdocs.org/ntsb/LAX91LA343.md): Piper PA-31-310 · Byron, CA · Accident · No injuries · Limited investigation · Final report · Aug 3, 1991 · N504DB · Substantial damage
  > The pilot's failure to refuel the airplane and his misjudging the distance to the runway.
- [NTSB FTW91LA140](https://openairdocs.org/ntsb/FTW91LA140.md): Beech K35 · Laredo, TX · Accident · Minor injuries · Limited investigation · Final report · Aug 3, 1991 · N8111R · Substantial damage
  > The improper installation of the oil filter adaptor 'o' ring (seal) by other maintenance personnel who distorted it. A factor was the rough, uneven terrain.
- [NTSB CHI91LA250](https://openairdocs.org/ntsb/CHI91LA250.md): Piper PA-12 · Loman, MN · Accident · No injuries · Limited investigation · Final report · Aug 3, 1991 · CFAOQ · Substantial damage
  > Fuel exhaustion due to fuel consumption calculations misjudged by the pilot.
- [NTSB SEA91LA198](https://openairdocs.org/ntsb/SEA91LA198.md): Chance Vought F4U-4 · Chiloquin, OR · Accident · Serious injuries · Limited investigation · Final report · Aug 2, 1991 · N5222V · Destroyed
  > The loss of power due to engine failure, for undetermined reasons.
- [NTSB LAX91FA344](https://openairdocs.org/ntsb/LAX91FA344.md): Cessna 182P · Lovelock, NV · Accident · 1 fatal · Field investigation · Final report · Aug 2, 1991 · N1315S · Destroyed
  > Failure of the pilot to maintain sufficient altitude for obstruction clearance, and his inadequate visual scan.
- [NTSB FTW91LA141](https://openairdocs.org/ntsb/FTW91LA141.md): Cessna 172F · Cumby, TX · Accident · No injuries · Limited investigation · Final report · Aug 2, 1991 · N5524R · Substantial damage
  > Power loss due to a blocked fuel vent system. A factor was the lack of suitable terrain for the forced landing.
- [NTSB CHI91LA242](https://openairdocs.org/ntsb/CHI91LA242.md): American AA1 · Spearville, KS · Accident · Minor injuries · Limited investigation · Final report · Aug 2, 1991 · N6108L · Substantial damage
  > The pilot's selection of unsuitable terrain on which to perform a precautionary landing. Factors related to the accident were poor in flight/planning decision which resulted in the pilot becoming lost/disoriented.
- [NTSB ANC91LA113](https://openairdocs.org/ntsb/ANC91LA113.md): Mooney M-20F · Wood River, AK · Accident · No injuries · Limited investigation · Final report · Aug 2, 1991 · N6848V · Substantial damage
  > The failure of the number 4 cylinder connecting rod cop due to fatigue. Contributing to the accident was the rough surface of the forced landing area.
- [NTSB NYC91LA200](https://openairdocs.org/ntsb/NYC91LA200.md): Piper PA-12 · Alton, NH · Accident · No injuries · Limited investigation · Final report · Aug 1, 1991 · N4436M · Substantial damage
  > The pilot's improper use of carburetor heat, which resulted in a loss of engine power.
- [NTSB BFO91LA071](https://openairdocs.org/ntsb/BFO91LA071.md): Cessna 172G · Fredericksburg, VA · Accident · No injuries · Limited investigation · Final report · Aug 1, 1991 · N6002R · Substantial damage
  > The pilot's selection of the improper fuel tank. Contributing to the accident was the pilot did not use the check list.
- [NTSB ATL91FA148](https://openairdocs.org/ntsb/ATL91FA148.md): Cessna 401 · Monroe, NC · Accident · 1 fatal · Field investigation · Final report · Aug 1, 1991 · N3298Q · Substantial damage
  > Inadequate preflight by the pilot, which resulted in fuel exhaustion, due to an inadequate supply of fuel. The pilot's lack of familiarity with the aircraft fuel system was a related factor.
- [NTSB NYC91FA193](https://openairdocs.org/ntsb/NYC91FA193.md): Piper PA-28-236 · Fogelsville, PA · Accident · 2 fatal · Field investigation · Final report · Jul 31, 1991 · N28568 · Destroyed
  > The improper decision by the non-instrument rated pilot to attempt VFR flight in instrument meteorological conditions, which resulted in a loss of airplane control. Factors related to the accident were: the pilot's overconfidence in his ability, his lack of…
- [NTSB CHI91LA237](https://openairdocs.org/ntsb/CHI91LA237.md): Piper PA-28-140 · Manning, IA · Accident · No injuries · Limited investigation · Final report · Jul 31, 1991 · N423FL · Substantial damage
  > The pilot's improper selection of fuel tanks and improper in-flight emergency procedure by the pilot.
- [NTSB CHI91LA232](https://openairdocs.org/ntsb/CHI91LA232.md): Cessna 305 · Hutchinson, KS · Accident · Serious injuries · Limited investigation · Final report · Jul 30, 1991 · N19KL · Substantial damage
  > Fuel consumption calculations misjudged by the pilot resulting in fuel exhaustion. Factors related to the accident were compensation for wind conditions were inadequate and presence of trees during the emergency landing attempt.
- [NTSB BFO91DLQ01](https://openairdocs.org/ntsb/BFO91DLQ01.md): Gordorn Price Ultimate 10-300 · Franklin, KY · Accident · Serious injuries · Final report · Jul 29, 1991 · N6521R · Substantial damage
  > Delay in switching fuel tanks which resulted in fuel exhaustion and loss of engine power.
- [NTSB ANC91LA112](https://openairdocs.org/ntsb/ANC91LA112.md): Pilatus Porter PC-6/350 · Yakutat, AK · Accident · No injuries · Limited investigation · Final report · Jul 29, 1991 · N4913 · Substantial damage
  > The fuel contamination and the pilot's inadequate preflight. Contributing to the accident was the soft sand bar.
- [NTSB NYC91LA191](https://openairdocs.org/ntsb/NYC91LA191.md): Beech C-23 · Williamstown, MA · Accident · No injuries · Limited investigation · Final report · Jul 28, 1991 · N7690R · Substantial damage
  > Engine failure as a result of improper engine overhaul performed by other maintenance personnel. A factor was the lack of suitable terrain.
- [NTSB SEA91LA193](https://openairdocs.org/ntsb/SEA91LA193.md): Beech N35 · Hillsboro, OR · Accident · No injuries · Limited investigation · Final report · Jul 27, 1991 · N9425Y · Substantial damage
  > Fuel starvation due to the improper use of the fuel selector switch by the pilot and his failure to extend the landing gear for the forced landing.
- [NTSB MIA91LA192](https://openairdocs.org/ntsb/MIA91LA192.md): Cessna 150M · Caribbean Sea · Accident · Minor injuries · Limited investigation · Final report · Jul 27, 1991 · N6088K · Substantial damage
  > Improper placement of the boost pump selector by the pilot in command, and electrical system failure for undetermined reasons. This resulted in the total loss of engine power due to fuel starvation.
- [NTSB LAX91LA339](https://openairdocs.org/ntsb/LAX91LA339.md): Aerospatiale AS350B · Kahului, HI · Accident · No injuries · Limited investigation · Final report · Jul 25, 1991 · N766MP · Substantial damage
  > A non-mechanical loss of engine power due to fuel exhaustion and subsequent hard landing by the pilot. Contributing to the accident was a malfunctioning fuel low level indication system.
- [NTSB FTW91LA127](https://openairdocs.org/ntsb/FTW91LA127.md): Piper PA-24-400 · Nashville, AR · Accident · Minor injuries · Limited investigation · Final report · Jul 25, 1991 · N8507P · Substantial damage
  > Fuel starvation induced loss of power due to a blocked finger fuel strainer in the fuel servo unit. A factor was the unsuitable terrain at the pilot's disposal.
- [NTSB FTW91DPJ03](https://openairdocs.org/ntsb/FTW91DPJ03.md): Grimm Cavalier SA102.5 · Mcalester, OK · Accident · 2 fatal · Final report · Jul 25, 1991 · N413P · Destroyed
  > The pilot's attempted flight into IMC and his subsequent loss of control due to spatial disorientation.
- [NTSB DEN91LA104](https://openairdocs.org/ntsb/DEN91LA104.md): Cessna 152 · Fountain, CO · Accident · No injuries · Limited investigation · Final report · Jul 24, 1991 · N24204 · Substantial damage
  > The pilot's selection of unsuitable terrain on which to make a landing. Factors were: the pilot's inadequate preflight planning, and weather conditions that included low ceiling, obscuration, fog, and drizzle.
- [NTSB DEN91FA113](https://openairdocs.org/ntsb/DEN91FA113.md): Cessna 182P · Redstone, CO · Accident · 1 fatal · Field investigation · Final report · Jul 24, 1991 · N20887 · Destroyed
  > An inflight collision with terrain after the pilot continued the flight into an area of clouds and rain.
- [NTSB BFO91FA068](https://openairdocs.org/ntsb/BFO91FA068.md): Beech V35A · Jonesville, VA · Accident · 4 fatal · Field investigation · Final report · Jul 24, 1991 · N118CB · Destroyed
  > Failure of the pilot-in-command (PIC) to assure that the instrument departure procedure was followed and that the aircraft remained clear of mountainous terrain.
- [NTSB ATL91LA141](https://openairdocs.org/ntsb/ATL91LA141.md): Maridon Starduster TOO · Locust Grove, GA · Accident · Serious injuries · Limited investigation · Final report · Jul 24, 1991 · N3263 · Substantial damage
  > Fuel exhaustion which resulted from the failure of the pilots to refuel the airplane. A factor was the local pilot's having become lost.
- [NTSB NYC91LA185](https://openairdocs.org/ntsb/NYC91LA185.md): Piper PA-23-250 · Templeton, MA · Accident · No injuries · Limited investigation · Final report · Jul 22, 1991 · N54819 · Substantial damage
  > Fuel starvation induced power loss on first the left engine due to a failed fuel fitting and then the right engine due to a worn fuel fitting. A factor was the lack of suitable terrain for the forced landing.
- [NTSB LAX91LA320](https://openairdocs.org/ntsb/LAX91LA320.md): Sikorsky SK-58 · Daggett, CA · Accident · No injuries · Limited investigation · Final report · Jul 22, 1991 · N58WH · Substantial damage
  > The failure of an engine connecting rod causing a reduction of engine power to the point where level flight could not be maintained. A factor in the accident was the dark night conditions which restricted the pilot's ability to select the best landing site.
- [NTSB CHI91LA221](https://openairdocs.org/ntsb/CHI91LA221.md): Cessna 150M · Merrillville, IN · Accident · No injuries · Limited investigation · Final report · Jul 22, 1991 · N714EC · Substantial damage
  > Improper pre-flight planning and preparation by the pilot-in-command. Factors related to this accident were the pilot-in-commands's inattentiveness concerning the refueling of his airplane, and inadequate fuel supply, inattentive ground personnel, and…
- [NTSB CHI91IA223](https://openairdocs.org/ntsb/CHI91IA223.md): Beech B200 · Greenbay, WI · Incident · No injuries · Incident investigation · Final report · Jul 22, 1991 · N770M · Minor damage
  > Inadequate airframe design, which resulted in the in-flight separation of the left engine's outboard aft upper cowl door.
- [NTSB SEA91LA182](https://openairdocs.org/ntsb/SEA91LA182.md): Piper PA-20 · Ione, WA · Accident · 2 fatal · Limited investigation · Final report · Jul 21, 1991 · N7066K · Destroyed
  > Inadequate clearance. A factor to the accident was: poor inflight planning.
- [NTSB NYC91LA173](https://openairdocs.org/ntsb/NYC91LA173.md): Cessna A185F · Vernon, OH · Accident · Minor injuries · Limited investigation · Final report · Jul 21, 1991 · N185GS · Destroyed
  > The pilot rotated the airplane prematurely and continued the climb at a deck angle that eventually resulted in a stall. Factors related to the accident were: the pilot's complacency, failure to determine the airplane's performance capabilities prior to take…
- [NTSB LAX91LA321](https://openairdocs.org/ntsb/LAX91LA321.md): Piper PA 18-135 · Gerlach, NV · Accident · No injuries · Limited investigation · Final report · Jul 21, 1991 · N9977Q · Substantial damage
  > The failure of the pilot to maintain adequate terrain clearance by the selection of an inappropriate cruise altitude resulting in an in flight collision with terrain.
- [NTSB SEA91LA190](https://openairdocs.org/ntsb/SEA91LA190.md): Fleet FL-80 · Havre, MT · Accident · Minor injuries · Limited investigation · Final report · Jul 20, 1991 · CFDPZ · Substantial damage
  > The engine driven fuel injection pump metering valve shaft was loose. A factor to the accident was: inadequate annual inspection.
- [NTSB SEA91LA189](https://openairdocs.org/ntsb/SEA91LA189.md): Beech V35A · Weiser, ID · Accident · No injuries · Limited investigation · Final report · Jul 20, 1991 · N8081R · Substantial damage
  > The pilot did not refuel the airplane resulting in fuel exhaustion.
- [NTSB NYC91LA183](https://openairdocs.org/ntsb/NYC91LA183.md): Beech B90 · Waynesville, OH · Accident · Serious injuries · Limited investigation · Final report · Jul 20, 1991 · N9HW · Substantial damage
  > The shroud lines from the parachute cutting through the left horizontal stabilizer and deforming the left elevator after the jumper had an uncommanded deployment of his reserve parachute and was pulled from the airplane.
- [NTSB LAX91LA323](https://openairdocs.org/ntsb/LAX91LA323.md): Cessna C-172P · Hesperia, CA · Accident · No injuries · Limited investigation · Final report · Jul 20, 1991 · N54694 · Substantial damage
  > A stuck engine throttle due to improper maintenance procedures.
- [NTSB SEA91FA181](https://openairdocs.org/ntsb/SEA91FA181.md): Cessna 180J · Newcastle, WY · Accident · 2 fatal · Field investigation · Final report · Jul 19, 1991 · N9962N · Destroyed
  > Pilot factor in that he did not maintain sufficient flying speed and allowed the aircraft to enter an inadvertent stall/spin. Factors include high density altitude.
- [NTSB FTW91DPG15](https://openairdocs.org/ntsb/FTW91DPG15.md): Grumman 164B · Brinkley, AR · Accident · No injuries · Final report · Jul 19, 1991 · N8491K · Destroyed
  > A blocked fuel screen which resulted in a fuel starvation induced loss of power. A factor was the lack of suitable terrain for the forced landing.

Next page: https://openairdocs.org/ntsb-phases/400/cases.md?page=262

## The whole list in SQL

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

```sql
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
```

This list as a web page: https://openairdocs.org/ntsb-phases/400/cases?page=261

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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.