# NTSB investigations, MO: Takeoff

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 1 of 6 · 282 cases

## Latest cases

- [NTSB CEN26LA239](https://openairdocs.org/ntsb/CEN26LA239.md): Cessna T206H · Ava, MO · Accident · No injuries · Class 4 · Limited · Investigation open · Jun 29, 2026 · N480AC · Substantial damage
- [NTSB WPR26LA229](https://openairdocs.org/ntsb/WPR26LA229.md): Ryan Navion · Bismarck, MO · Accident · Minor injuries · Class 4 · Limited · Final report · Jun 23, 2026 · N4583K · Substantial damage
  > The pilot’s failure to remove the maintenance spacer before takeoff, which resulted in restricted flight control movement and a loss of control.
- [NTSB CEN26LA191](https://openairdocs.org/ntsb/CEN26LA191.md): Vertical Hummingbird · Lee's Summit, MO · Accident · Minor injuries · Class 3 · Limited · Preliminary report · May 16, 2026 · N284ST · Substantial damage
  > On May 16, 2026, about 0950 central daylight time, a Vertical Aviation Technologies 300L Hummingbird helicopter, N284ST, was substantially damaged when it was involved in an accident near Lee’s Summit, Missouri. One passenger sustained minor injuries. The…
- [NTSB CEN26FA140](https://openairdocs.org/ntsb/CEN26FA140.md): Aero Commander 500-B · Chesterfield, MO · Accident · 1 fatal · Class 3 · Field · Preliminary report · Mar 17, 2026 · N444CA · Destroyed
  > On March 17, 2026, about 0024 central daylight time, an Aero Commander 500-B airplane, N444CA, was destroyed when it was involved in an accident near Chesterfield, Missouri. The pilot was fatally injured. The airplane was operated as a Title 14 Code of…
- [NTSB CEN24LA315](https://openairdocs.org/ntsb/CEN24LA315.md): Grumman American Avn. AA-5B · Camdenton, MO · Accident · No injuries · Class 3 · Limited · Final report · Jul 11, 2024 · N23JK · Substantial damage
  > The inadequate maintenance of the seat locking mechanism, which resulted in the pilot’s seat sliding back during takeoff and a subsequent loss of control.
- [NTSB CEN24LA159](https://openairdocs.org/ntsb/CEN24LA159.md): Cirrus Design SR20 · Chesterfield, MO · Accident · No injuries · Class 4 · Limited · Final report · Apr 13, 2024 · N594M · Substantial damage
  > The student pilot’s failure to maintain control during takeoff. Contributing to the accident was the flight instructor’s delayed remedial action.
- [NTSB CEN24LA008](https://openairdocs.org/ntsb/CEN24LA008.md): Cubcrafters CC11-160 · Warrenton, MO · Accident · No injuries · Class 4 · Limited · Final report · Oct 8, 2023 · N211BL · Substantial damage
  > The pilot’s failure to maintain directional control during the touch-and-go landing. Contributing was the pilot’s decision to land with a quartering tailwind.
- [NTSB CEN23LA365](https://openairdocs.org/ntsb/CEN23LA365.md): Cessna A188B · Chillicothe, MO · Accident · No injuries · Class 4 · Limited · Final report · Aug 11, 2023 · N9237R · Substantial damage
  > The pilot’s decision to operate the airplane with a known tailwheel anomaly, which resulted in a loss of directional control.
- [NTSB CEN23FA314](https://openairdocs.org/ntsb/CEN23FA314.md): Piper PA-31P · Kearney, MO · Accident · 1 fatal · Class 3 · Field · Final report · Jul 20, 2023 · N200RA · Destroyed
  > The pilot’s decision to operate an airplane with known fuel leaks, his failure to conduct an engine run-up before takeoff, his subsequent failure to abort the takeoff, and the mechanic’s inadequate maintenance, which resulted in a partial loss of right engine…
- [NTSB CEN23FA304](https://openairdocs.org/ntsb/CEN23FA304.md): Piper PA28 · Osage Beach, MO · Accident · 2 fatal · Class 3 · Field · Final report · Jul 13, 2023 · N8225N · Substantial damage
  > The pilot’s failure to properly set the stabilator trim before takeoff, which resulted in an exceedance of the airplane’s critical angle of attack and an aerodynamic stall during takeoff.
- [NTSB CEN23LA196](https://openairdocs.org/ntsb/CEN23LA196.md): Piper PA-28-181 · Kansas City, MO · Accident · No injuries · Class 4 · Limited · Final report · May 22, 2023 · N227XY · Substantial damage
  > The student pilot's failure to maintain directional control during takeoff.
- [NTSB CEN22LA412](https://openairdocs.org/ntsb/CEN22LA412.md): Zenith 750 · Silex, MO · Accident · Serious injuries · Class 3 · Limited · Final report · Sep 7, 2022 · N1949H · Substantial damage
  > The pilot’s failure to maintain clearance from the powerlines during takeoff.
- [NTSB CEN21LA053](https://openairdocs.org/ntsb/CEN21LA053.md): Trick Trikes Stss · Holden, MO · Accident · 1 fatal · Class 3 · Limited · Final report · Nov 11, 2020 · N5152E · Destroyed
  > The noncertificated pilot’s failure to maintain aircraft control during takeoff.
- [NTSB CEN20LA429](https://openairdocs.org/ntsb/CEN20LA429.md): Cessna 172 · Higginsville, MO · Accident · No injuries · Class 4 · Limited · Final report · Sep 30, 2020 · N461CM · Substantial damage
  > The airplane’s collision with a deer on the runway during takeoff at night.
- [NTSB CEN20CA184](https://openairdocs.org/ntsb/CEN20CA184.md): Rhoads, Larry E Sopwith Baby · Lee's Summit, MO · Accident · No injuries · Class 4 · Data collection · Final report · May 19, 2020 · N41LR · Substantial damage
  > The airplane builder's improper installation of the lower right wing which resulted in an uncommanded left roll and the subsequent loss of control.
- [NTSB CEN20LA149](https://openairdocs.org/ntsb/CEN20LA149.md): Cessna 402 · Kirksville, MO · Accident · No injuries · Class 3 · Limited · Final report · Apr 14, 2020 · N98649 · Substantial damage
  > A loss of engine power after takeoff for undetermined reasons.
- [NTSB CEN19LA229](https://openairdocs.org/ntsb/CEN19LA229.md): Cessna 305A · Houston, MO · Accident · No injuries · Class 3 · Limited · Final report · Jul 21, 2019 · N1831 · Substantial damage
  > A total loss of engine power during initial climb due to carburetor icing, which resulted in a forced landing and impact with trees and terrain.
- [NTSB GAA19CA331](https://openairdocs.org/ntsb/GAA19CA331.md): Cessna 150 · Lee's Summit, MO · Accident · Minor injuries · Data collection · Final report · Jun 7, 2019 · N704HS · Substantial damage
  > The student pilot’s exceedance of the airplane's critical angle of attack during takeoff, which resulted in an aerodynamic stall.
- [NTSB GAA19CA008](https://openairdocs.org/ntsb/GAA19CA008.md): Cessna 188 · Rolla, MO · Accident · Minor injuries · Data collection · Final report · Oct 8, 2018 · N685JM · Substantial damage
  > The pilot's failure to maintain directional control during takeoff in a left quartering tailwind.
- [NTSB GAA18CA402](https://openairdocs.org/ntsb/GAA18CA402.md): Piper PA28 · Rolla, MO · Accident · No injuries · Data collection · Final report · Jun 28, 2018 · N7104F · Substantial damage
  > A collision with a deer on the runway during the takeoff roll at night.
- [NTSB OPS18IA014](https://openairdocs.org/ntsb/OPS18IA014.md): Embraer EMB145 · Springfield, MO · Incident · Class 3 · Incident · Final report · Jun 27, 2018 · N655AE · No damage
  > The local controller failing to follow established facility directives and issuing a clearance for takeoff from a runway not under his control.
- [NTSB CEN18LA194](https://openairdocs.org/ntsb/CEN18LA194.md): Air Tractor AT 502B · Qulin, MO · Accident · No injuries · Limited investigation · Final report · May 27, 2018 · N6180J · Substantial damage
  > The pilot’s improper weight-and-balance calculations and his decision to take off with the airplane at a high gross weight in high density altitude conditions, which resulted in an attempted takeoff that exceeded the airplane’s performance capability. Also…
- [NTSB CEN18LA065](https://openairdocs.org/ntsb/CEN18LA065.md): Piper PA-28-201T · Versailles, MO · Accident · No injuries · Limited investigation · Final report · Dec 19, 2017 · N555WM · Substantial damage
  > The total loss of engine power due to fuel starvation when the cap fitting came off the inlet tee fitting on the throttle body/fuel metering unit.
- [NTSB GAA17CA532](https://openairdocs.org/ntsb/GAA17CA532.md): Cessna 177 · Harrisonville, MO · Accident · No injuries · Data collection · Final report · Sep 12, 2017 · N34413 · Substantial damage
  > A collision with a deer on the runway during the takeoff roll.
- [NTSB GAA17CA498](https://openairdocs.org/ntsb/GAA17CA498.md): Luscombe 8 · Perryville, MO · Accident · Minor injuries · Data collection · Final report · Aug 21, 2017 · N2861K · Substantial damage
  > The pilot’s failure to maintain directional control during takeoff.
- [NTSB GAA17CA476](https://openairdocs.org/ntsb/GAA17CA476.md): Cessna 172 · Drexel, MO · Accident · No injuries · Data collection · Final report · Aug 5, 2017 · N8226U · Substantial damage
  > The pilot’s failure to maintain adequate airspeed and his exceedance of the airplane’s critical angle of attack, which resulted in an aerodynamic stall.
- [NTSB CEN17LA303](https://openairdocs.org/ntsb/CEN17LA303.md): Cessna A188B · Marshall, MO · Accident · No injuries · Limited investigation · Final report · Aug 4, 2017 · N3047J · Substantial damage
  > The pilot's inability to accurately monitor the airplane's airspeed after takeoff due to an inoperative airspeed indicator, which resulted in the pilot's failure to maintain adequate airspeed and his exceedance of the airplane's critical angle of attack and…
- [NTSB CEN17LA293](https://openairdocs.org/ntsb/CEN17LA293.md): Chapman T-BIRD II · Potosi, MO · Accident · Serious injuries · Limited investigation · Final report · Jul 31, 2017 · N204BC · Substantial damage
  > The pilot's loss of airplane control during a departure turn for reasons that could not be determined.
- [NTSB CEN17LA206](https://openairdocs.org/ntsb/CEN17LA206.md): Kenneth B Hines Nieuport 28 · Boonville, MO · Accident · No injuries · Limited investigation · Final report · Jun 1, 2017 · N6165 · Substantial damage
  > A partial loss of engine power due to a compromised induction system.
- [NTSB CEN17LA061](https://openairdocs.org/ntsb/CEN17LA061.md): Mead RV 8A · Farmington, MO · Accident · Minor injuries · Limited investigation · Final report · Dec 27, 2016 · N918KS · Substantial damage
  > The pilot's failure to maintain airplane control during takeoff in crosswind conditions.
- [NTSB CEN17LA031](https://openairdocs.org/ntsb/CEN17LA031.md): Piper PA 28-236 · Lexington, MO · Accident · No injuries · Limited investigation · Final report · Oct 27, 2016 · N4376V · Substantial damage
  > A total loss of engine power during takeoff for reasons that could not be determined based on available information.
- [NTSB CEN16FA378](https://openairdocs.org/ntsb/CEN16FA378.md): Piper PA 28-235 · Lee's Summit, MO · Accident · 2 fatal · Field investigation · Final report · Sep 20, 2016 · N8983W · Substantial damage
  > The pilot's improper control inputs during takeoff, which resulted in the exceedance of the airplane's critical angle of attack and subsequent departure stall, and loss of airplane control.
- [NTSB GAA15CA166](https://openairdocs.org/ntsb/GAA15CA166.md): Bryan Jerry R CH750 · Gainesville, MO · Accident · No injuries · Data collection · Final report · Jun 26, 2015 · N750AF · Substantial damage
  > The pilot's perception that the airplane was not climbing normally, which precipitated an aborted landing with insufficient runway remaining to stop the airplane safely.
- [NTSB CEN15CA158](https://openairdocs.org/ntsb/CEN15CA158.md): Piper PA 28-140 · Kansas City, MO · Accident · Minor injuries · Data collection · Final report · Mar 2, 2015 · N1513J · Substantial damage
  > The loss of engine power due to fuel starvation.
- [NTSB CEN15CA165](https://openairdocs.org/ntsb/CEN15CA165.md): Piper PA 28-181 · Lee's Summit, MO · Accident · No injuries · Data collection · Final report · Mar 1, 2015 · N3575X · Substantial damage
  > The pilot-receiving-instruction's excessive pitch control during takeoff, which resulted in an aerodynamic stall shortly after liftoff and the subsequent loss of control. Contributing to the accident was the flight crew's decision to have the flight…
- [NTSB CEN15LA050](https://openairdocs.org/ntsb/CEN15LA050.md): Cessna 401A · Fulton, MO · Accident · Serious injuries · Limited investigation · Final report · Nov 17, 2014 · N401ME · Substantial damage
  > A failure of the right engine magneto distributor drive gears, which resulted in a total loss of engine power during takeoff. Contributing to the accident was the operator’s failure to inspect and maintain the magnetos in accordance with the engine…
- [NTSB CEN14LA441](https://openairdocs.org/ntsb/CEN14LA441.md): Becker Elmer L Stol CH 750 · Grain Valley, MO · Accident · Serious injuries · Limited investigation · Final report · Aug 19, 2014 · N484XB · Substantial damage
  > The pilot’s failure to maintain airplane control during a low-speed, high-pitch climb after the airplane experienced a loss of electrical power and subsequent total loss of engine power, which resulted in an aerodynamic stall. Contributing to the accident was…
- [NTSB CEN14CA250](https://openairdocs.org/ntsb/CEN14CA250.md): Santschi Chris A Vans RV8 · Bonne Terre, MO · Accident · No injuries · Data collection · Final report · May 16, 2014 · N627CS · Substantial damage
  > The pilot's failure to maintain aircraft control on takeoff.
- [NTSB ENG14IA005](https://openairdocs.org/ntsb/ENG14IA005.md): Boeing 737 3H4 · St. Louis, MO · Incident · No injuries · Incident investigation · Final report · Dec 23, 2013 · N360SW · Minor damage
  > The initial damage to the fan blades was caused by the ingestion of two mallard ducks that caused one or more fan blades to fracture, striking the fan shroud, as well as other passing fan blades, producing various sized blades fragments that created a…
- [NTSB CEN13CA386](https://openairdocs.org/ntsb/CEN13CA386.md): Piper PA-28-140 · Climax Springs, MO · Accident · No injuries · Data collection · Final report · Jun 30, 2013 · N6674W · Substantial damage
  > The pilot’s inadequate planning and poor decision to attempt to take off on a runway from which the airplane could not obtain flight.
- [NTSB CEN12CA613](https://openairdocs.org/ntsb/CEN12CA613.md): Beech A36 · Washington, MO · Accident · No injuries · Data collection · Final report · Aug 7, 2012 · N41HC · Substantial damage
  > The pilot raised the landing gear handle instead of the flap handle during a touch-and-go landing, resulting in the collapse of the nose landing gear while accelerating to takeoff.
- [NTSB CEN12CA361](https://openairdocs.org/ntsb/CEN12CA361.md): Cessna 172H · Moscow Mills, MO · Accident · No injuries · Data collection · Final report · Jun 10, 2012 · N3736R · Substantial damage
  > The pilot's failure to maintain control of the airplane during takeoff in a gusty crosswind, which resulted in a runway excursion.
- [NTSB CEN12LA353](https://openairdocs.org/ntsb/CEN12LA353.md): Schweizer 269C-1 · Chesterfield, MO · Accident · No injuries · Limited investigation · Final report · May 26, 2012 · N345MH · Substantial damage
  > The undercharged and overcharged landing gear dampers, which allowed initiation of the ground resonance event from which the pilot was unable to recover due to his limited experience in helicopters. Contributing to the accident was the ineffective damper…
- [NTSB CEN12FA188](https://openairdocs.org/ntsb/CEN12FA188.md): Piper PA-28-161 · Mexico, MO · Accident · 1 fatal · Field investigation · Final report · Mar 18, 2012 · N158EA · Substantial damage
  > The pilot’s failure to maintain airplane control during takeoff, which resulted in an aerodynamic stall and subsequent collision with trees. Contributing to the accident was the pilot’s inadequate preflight performance planning before departing on the soft,…
- [NTSB CEN12LA114](https://openairdocs.org/ntsb/CEN12LA114.md): Southern Powered Parachute Condor · Rogersville, MO · Accident · Serious injuries · Limited investigation · Final report · Dec 25, 2011 · UNREG · Substantial damage
  > The pilot's inadequate preflight inspection of the takeoff area, which resulted in a loss of control due to the binding of the parachute's lines.
- [NTSB CEN12LA056](https://openairdocs.org/ntsb/CEN12LA056.md): Cessna 182K · Branson West, MO · Accident · No injuries · Limited investigation · Final report · Oct 30, 2011 · N2893R · Substantial damage
  > The pilot's failure to ensure that his seat was in a locked position before takeoff, which resulted in the seat sliding rearward and the subsequent loss of directional control.
- [NTSB CEN11CA589](https://openairdocs.org/ntsb/CEN11CA589.md): Air Tractor AT-502B · Matthews, MO · Accident · No injuries · Data collection · Final report · Aug 22, 2011 · N113AA · Substantial damage
  > The pilot's failure to maintain control of the airplane during takeoff.
- [NTSB CEN11CA576](https://openairdocs.org/ntsb/CEN11CA576.md): Piper PA-28-235 · Stanberry, MO · Accident · No injuries · Data collection · Final report · Aug 14, 2011 · N42860 · Substantial damage
  > The pilot’s failure to maintain directional control during takeoff.
- [NTSB CEN11FA118](https://openairdocs.org/ntsb/CEN11FA118.md): Eurocopter AS350-B2 · La Monte, MO · Accident · Serious injuries · Field investigation · Final report · Dec 19, 2010 · N549AM · Substantial damage
  > An interruption of fuel to the engine due to air in the fuel lines, which resulted in an engine flameout and the total loss of engine power. The reason for air in the fuel line resulting in an engine flameout could not be determined because postaccident…
- [NTSB CEN10CA481](https://openairdocs.org/ntsb/CEN10CA481.md): Oliver A Bruce RV6-A · Trenton, MO · Accident · Serious injuries · Data collection · Final report · Aug 15, 2010 · N50BU · Substantial damage
  > The canopy opening shortly after takeoff due to an inadequate repair and subsequent failure of the canopy latch, resulting in a emergency landing. Contributing to the accident was the lack of available runway remaining for the forced landing.

Next page: https://openairdocs.org/ntsb-phases/300/cases.md?state=MO&page=2

## 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."eventStateOrRegion" = 'MO' AND c."eventCountry" = 'USA'
  AND c."mKey" IN (SELECT case_mkey FROM case_phases WHERE main = 300)
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb-phases/300/cases?state=MO

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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.
