# NTSB investigations: Amateur-built UNKNOWN ENG, CO

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 2 · 59 cases

## Latest cases

- [NTSB ANC26LA049](https://openairdocs.org/ntsb/ANC26LA049.md): William F Schoen RV-7 · Alpine, CO · Accident · Minor injuries · Class 4 · Limited · Investigation open · Jun 10, 2026 · N727BN · Substantial damage
- [NTSB CEN25LA405](https://openairdocs.org/ntsb/CEN25LA405.md): Sukhoi SU-26MX · Longmont, CO · Accident · Minor injuries · Class 4 · Limited · Final report · Sep 30, 2025 · N25SU · Substantial damage
  > The pilot's failure to maintain directional control during takeoff.
- [NTSB CEN24LA198](https://openairdocs.org/ntsb/CEN24LA198.md): Brant T Phillips Super Cub EXP · Franktown, CO · Accident · No injuries · Class 4 · Limited · Final report · May 26, 2024 · N983SB · Substantial damage
  > The pilot’s failure to maintain aircraft control during final approach and attempted go-around after encountering a sudden windshear.
- [NTSB CEN20CA311](https://openairdocs.org/ntsb/CEN20CA311.md): Air Tractor AT 401 · Burlington, CO · Accident · Minor injuries · Class 4 · Data collection · Final report · Jul 27, 2020 · N9190Q · Substantial damage
  > The pilot’s failure to maintain clearance from guy-wires during low-altitude agricultural operations.
- [NTSB CEN20CA277](https://openairdocs.org/ntsb/CEN20CA277.md): Kitfox Kitfox Sport · Rand, CO · Accident · Minor injuries · Class 4 · Data collection · Final report · Jul 12, 2020 · N702KS · Substantial damage
  > The encounter with the downdrafts during the attempted takeoff, which resulted in decreased airplane's climb performance and subsequent impact with terrain.
- [NTSB CEN20LA278](https://openairdocs.org/ntsb/CEN20LA278.md): Grumman G164 · Springfield, CO · Accident · 1 fatal · Class 3 · Limited · Final report · Jul 10, 2020 · N6917K · Destroyed
  > The pilot’s loss of visibility in the cockpit due to foam created by the chemicals loaded in the hopper, which resulted in collision with terrain. Contributing to the accident was the combining of chemicals known to produce foam and the pilot’s failure to…
- [NTSB GAA19CA262](https://openairdocs.org/ntsb/GAA19CA262.md): Cub Crafters Carbon CUB EX · Grand Junction, CO · Accident · No injuries · Data collection · Final report · May 11, 2019 · N56XC · Substantial damage
  > The pilot's failure to maintain clearance from power lines during low-level maneuvering through a canyon.
- [NTSB CEN18LA080](https://openairdocs.org/ntsb/CEN18LA080.md): Tomlinson Tracy L Tukan · Erie, CO · Accident · Minor injuries · Limited investigation · Final report · Jan 18, 2018 · N907T · Substantial damage
  > The student pilot’s inadvertent shutting off of the fuel valve while on approach, which resulted in a loss of engine power due to fuel starvation and impact with terrain.
- [NTSB GAA17CA257](https://openairdocs.org/ntsb/GAA17CA257.md): Nelson Sydney Vans Acft RV8A · Englewood, CO · Accident · Minor injuries · Data collection · Final report · May 4, 2017 · N832SD · Substantial damage
  > The pilot's improper landing flare and inadvertent selection of the mixture control, which resulted in a hard, bounced landing during gusting crosswind wind conditions.
- [NTSB CEN16FA331](https://openairdocs.org/ntsb/CEN16FA331.md): Stemme S10 VT · Telluride, CO · Accident · 2 fatal · Field investigation · Final report · Aug 24, 2016 · N5021 · Substantial damage
  > The pilot's encounter with a downdraft that exceeded the climb performance of the powered glider and resulted in his inability to maintain clearance from the trees. Contributing to the accident was the pilot's decision to fly near building clouds and rain…
- [NTSB GAA16CA201](https://openairdocs.org/ntsb/GAA16CA201.md): Helicycle/Morrisey RR RM-1 · Denver, CO · Accident · Minor injuries · Data collection · Final report · Apr 22, 2016 · N867TV · Substantial damage
  > The pilot's failure to maintain control of the helicopter yaw while operating in conditions conducive to loss of tail rotor effectiveness, resulting in an uncommanded rapid right yaw and ground impact.
- [NTSB GAA16CA061](https://openairdocs.org/ntsb/GAA16CA061.md): Melvin K Callen Backcountry Supercub · Fort Morgan, CO · Accident · No injuries · Data collection · Final report · Nov 24, 2015 · N842MC · Substantial damage
  > The pilot's excessive braking during the landing roll, which resulted in a nose over.
- [NTSB CEN15LA084](https://openairdocs.org/ntsb/CEN15LA084.md): Enstrom 280FX · Fort Lupton, CO · Accident · Minor injuries · Limited investigation · Final report · Dec 8, 2014 · N409LH · Substantial damage
  > The loss of engine power during cruise flight for reasons that could not be determined based on the available information.
- [NTSB CEN13LA488](https://openairdocs.org/ntsb/CEN13LA488.md): Griffith E/Boyd W E Lancair 360 · Nucla, CO · Accident · No injuries · Limited investigation · Final report · Aug 12, 2013 · N15EG · Substantial damage
  > The pilot’s failure to extend the airplane’s landing gear before landing.
- [NTSB CEN13LA368](https://openairdocs.org/ntsb/CEN13LA368.md): Nanchang China CJ-6 · Wolcott, CO · Accident · 2 fatal · Limited investigation · Final report · Jun 23, 2013 · N2726C · Substantial damage
  > The pilots decision to perform an aerobatic maneuver at a low altitude from which he was unable to recover.
- [NTSB CEN12LA668](https://openairdocs.org/ntsb/CEN12LA668.md): Thompson RV-6 · Pagosa Springs, CO · Accident · No injuries · Limited investigation · Final report · Sep 20, 2012 · N140RV · Substantial damage
  > The pilot’s failure to maintain directional control of the airplane during the landing roll. Contributing to the accident was the pilot’s lack of landing experience at high density altitudes.
- [NTSB CEN12FA462](https://openairdocs.org/ntsb/CEN12FA462.md): Nanchang China CJ-6A · Walsenburg, CO · Accident · 2 fatal · Field investigation · Final report · Jul 21, 2012 · N96YK · Substantial damage
  > The pilot's failure to maintain airplane control while turning from base to final leg in the traffic pattern.
- [NTSB CEN12CA442](https://openairdocs.org/ntsb/CEN12CA442.md): Doppelt Fredric F F. 8L Falco · Durango, CO · Accident · Minor injuries · Data collection · Final report · Jul 15, 2012 · N532FD · Substantial damage
  > The pilot's failure to maintain control of the airplane and the instructor's delayed remedial action.
- [NTSB CEN12LA389](https://openairdocs.org/ntsb/CEN12LA389.md): Hoyle Fighter Escort Wings · Pueblo, CO · Accident · No injuries · Limited investigation · Final report · Jun 23, 2012 · N2051P · Substantial damage
  > An internal failure of one of the electrical system’s two batteries combined with the inadequate electrical system design, which resulted in a total loss of engine power.
- [NTSB CEN12LA374](https://openairdocs.org/ntsb/CEN12LA374.md): Yakovlev Yak-52 · Loveland, CO · Accident · No injuries · Limited investigation · Final report · Jun 14, 2012 · N76YK · Substantial damage
  > The pilot’s inadvertent closure of the pneumatic system valve, which resulted in the nose landing gear not fully extending before landing. Contributing to the accident was the pilot's reliance on the mechanical landing gear position indicators instead of the…
- [NTSB CEN12CA263](https://openairdocs.org/ntsb/CEN12CA263.md): Campbell David Legacy · Durango, CO · Accident · No injuries · Data collection · Final report · May 1, 2012 · N12KX · Substantial damage
  > The pilot’s improper flare and subsequent aerodynamic stall, which resulted in a hard landing.
- [NTSB CEN10CA376](https://openairdocs.org/ntsb/CEN10CA376.md): Wells Terry Hula Girl · Wellington, CO · Accident · No injuries · Data collection · Final report · Jul 3, 2010 · N301TW · Substantial damage
  > A partial loss of engine power due to the inadequate design of the engine cowling.
- [NTSB CEN10LA242](https://openairdocs.org/ntsb/CEN10LA242.md): Jorritsma Jerrold S Berkut · Loveland, CO · Accident · No injuries · Limited investigation · Final report · May 9, 2010 · N3255U · Substantial damage
  > A loss of engine power due to a malfunction of the fuel controller resulting in a compressor stall.
- [NTSB CEN10FA115](https://openairdocs.org/ntsb/CEN10FA115.md): Piper PA-25-235 · Boulder, CO · Accident · 3 fatal · Field investigation · Final report · Feb 6, 2010 · N8718L · 3 aircraft · Substantial damage
  > The failure of both pilots to see and avoid the other resulting in a midair collision. Contributing to the accident was the lack of perceived visual relative motion of the Piper and the Cirrus to the pilot of each airplane, the terrain background, and the…
- [NTSB CEN09CA257](https://openairdocs.org/ntsb/CEN09CA257.md): Enstrom 280FX · Dacono, CO · Accident · No injuries · Data collection · Final report · Apr 20, 2009 · N409LH · Substantial damage
  > A partial loss of engine power for undetermined reasons.
- [NTSB CEN09LA075](https://openairdocs.org/ntsb/CEN09LA075.md): Hauser U/Hauser J KIT FOX CL · Boulder, CO · Accident · Minor injuries · Limited investigation · Final report · Nov 24, 2008 · N4JU · Substantial damage
  > A loss of engine thrust due to the pilot's inadvertent activation of the propeller controls. Contributing to the accident were the non-standard propeller controls and the pilot's lack of experience in the airplane.
- [NTSB DEN08CA045](https://openairdocs.org/ntsb/DEN08CA045.md): Piper PA-46-310P · Gunnison, CO · Accident · No injuries · Data collection · Final report · Dec 29, 2007 · N33MF · Substantial damage
  > The pilot's failure to maintain directional control of the airplane during takeoff resulting in the airplane hitting a snowbank and subsequently, the ground.
- [NTSB DEN07LA098](https://openairdocs.org/ntsb/DEN07LA098.md): Boeing 757-251 · Denver, CO · Accident · Serious injuries · Limited investigation · Final report · Jun 3, 2007 · N523US · No damage
  > The inadvertent encounter with moderate turbulence during the approach which resulted in a serious injury to the flight attendant
- [NTSB DEN07FA089](https://openairdocs.org/ntsb/DEN07FA089.md): Schleicher Alexander ASH 26E · Castle Rock, CO · Accident · 1 fatal · Field investigation · Final report · Apr 29, 2007 · N123KS · Substantial damage
  > the pilot's failure to maintain aircraft control resulting in an inadvertent stall/mush.
- [NTSB DEN05IA083](https://openairdocs.org/ntsb/DEN05IA083.md): McDonnell Douglas DC-9-82 · Denver, CO · Incident · No injuries · Incident investigation · Final report · May 28, 2005 · N911TW · Minor damage
  > the reason for the occurrence was not determined.
- [NTSB DEN05IA025](https://openairdocs.org/ntsb/DEN05IA025.md): Blair-American USA · Fort Collins, CO · Incident · No injuries · Incident investigation · Final report · Nov 12, 2004 · N1518 · 2 aircraft · No damage
  > the Blair-American and the Cessna pilot's inadequate visual lookout, and student pilot's failure to give right-of-way to a landing aircraft, which resulted in a runway incursion and subsequent collision. Contributing factors include the student instructor's…
- [NTSB DEN04LA108](https://openairdocs.org/ntsb/DEN04LA108.md): Davis-Zenair Stol CH 801 · Erie, CO · Accident · No injuries · Limited investigation · Final report · Jul 21, 2004 · N10627 · Substantial damage
  > impact with terrain during a forced landing following a loss of engine power for underdetermined reasons. A contributing factor was the lack of suitable terrain for a forced landing.
- [NTSB DEN04CA101](https://openairdocs.org/ntsb/DEN04CA101.md): Whitlock Rotorway Exec 162F · Meeker, CO · Accident · No injuries · Data collection · Final report · Jul 10, 2004 · N518W · Substantial damage
  > aircraft control not maintained by the pilot. A contributing factor was the failure of the supercharger.
- [NTSB DEN03LA129](https://openairdocs.org/ntsb/DEN03LA129.md): Davis Zenair Stol 701 · Aurora, CO · Accident · Minor injuries · Limited investigation · Final report · Jul 10, 2003 · N20584 · Substantial damage
  > the pilot's failure to attain adequate airspeed and establish a climb resulting in a stall/mush and collision with the ground. Contributing factors were his premature turn onto the downwind leg, and the plowed/furrowed terrain.
- [NTSB DEN02FA070](https://openairdocs.org/ntsb/DEN02FA070.md): Boone Rotorway 162-F · Englewood, CO · Accident · No injuries · Field investigation · Final report · Jul 9, 2002 · N30319 · Substantial damage
  > the pilot encountering settling with power. A factor contributing to the accident was the tailwind.
- [NTSB DEN01LA164](https://openairdocs.org/ntsb/DEN01LA164.md): Cessna 172RG · Englewood, CO · Accident · No injuries · Limited investigation · Final report · Sep 27, 2001 · N9320D · Substantial damage
  > the failure of the dual student to verify that the landing gear was down and locked, and the failure of the flight instructor to adequately supervise the dual student.
- [NTSB DEN01LA121](https://openairdocs.org/ntsb/DEN01LA121.md): Griffith-Boyd Lancair 360 · La Junta, CO · Accident · No injuries · Limited investigation · Final report · Jul 6, 2001 · N15EG · Substantial damage
  > a wheels-up landing due to an uncommanded gear retraction resulting from a short circuit of the landing gear electrical wiring.
- [NTSB DEN99LA068](https://openairdocs.org/ntsb/DEN99LA068.md): Weatherly 201-C · Two Buttes, CO · Accident · No injuries · Limited investigation · Final report · Apr 28, 1999 · N9095W · Substantial damage
  > The pilot's selection of an unsuitable landing area. Factors associated with the accident were an unknown object in the landing area, a failure of a main landing gear tire, and the pilot's inadvertent ground loop/swerve.
- [NTSB FTW97LA079](https://openairdocs.org/ntsb/FTW97LA079.md): Hughes 369HS · Wellington, CO · Accident · Minor injuries · Limited investigation · Final report · Jan 7, 1997 · N9089F · Destroyed
  > The pilot's failure to maintain control of the aircraft and his improper autorotation technique that induced the roll and subsequent ground collision. A factor was his lack of recurrent training.
- [NTSB FTW96LA360](https://openairdocs.org/ntsb/FTW96LA360.md): Cresap Early Bird Jenny · Kersey, CO · Accident · Minor injuries · Limited investigation · Final report · Aug 25, 1996 · N12JN · Destroyed
  > Failure of the throttle linkage. A related factor was the lack of suitable terrain for the forced landing.
- [NTSB FTW95LA405](https://openairdocs.org/ntsb/FTW95LA405.md): Let Blanik L-13 · Como, CO · Accident · Minor injuries · Limited investigation · Final report · Sep 24, 1995 · N38924 · Substantial damage
  > The pilot allowing the glider to develop an excessive descent rate. A factor was the premature and automatic disengagement of the winch-tow system.
- [NTSB DEN93LA086](https://openairdocs.org/ntsb/DEN93LA086.md): Balloon Works 7B-15 · Colorado Sprgs, CO · Accident · Serious injuries · Limited investigation · Final report · Jul 24, 1993 · N9067Y · No damage
  > The passenger's failure to assume the proper landing position as instructed by the pilot in command. A factor was: the high wind.
- [NTSB DEN93LA065](https://openairdocs.org/ntsb/DEN93LA065.md): Cessna 182A · Stratton, CO · Accident · No injuries · Limited investigation · Final report · Jun 3, 1993 · N2131G · Substantial damage
  > The selection of unsuitable terrain for a precautionary landing by the pilot in command. A factor was: misjudging the deteriorating weather.
- [NTSB DEN92IA014](https://openairdocs.org/ntsb/DEN92IA014.md): Cessna 172RG · Broomfield, CO · Incident · No injuries · Incident investigation · Final report · Dec 5, 1991 · N9320D · Minor damage
  > Failure of the left main landing gear pivot assembly due to ductile torsional overstress.
- [NTSB DEN89LA088](https://openairdocs.org/ntsb/DEN89LA088.md): Miller S.A.L. 2/3 Mustang · Erie, CO · Accident · Minor injuries · Limited investigation · Final report · Mar 19, 1989 · N51RM · Substantial damage
  > Loss of engine power for an unknown reason. Soft uneven terrain was a contributing factor.
- [NTSB DEN87LA236](https://openairdocs.org/ntsb/DEN87LA236.md): Let L-13 · Buena Vista, CO · Accident · No injuries · Limited investigation · Final report · Sep 5, 1987 · N38924 · Substantial damage
  > The plt was ferrying the glider to Buena Vista, Colorado & had previously obtained permission to land on a closed rwy. After being towed to the Buena Vista area, he released the glider from the tow plane & flew in the local area for about 40 min. He then…
- [NTSB DEN87LA124](https://openairdocs.org/ntsb/DEN87LA124.md): Brantly Helicopter 305 · Golden, CO · Accident · No injuries · Limited investigation · Final report · May 14, 1987 · N5JM · Substantial damage
  > The commercial plt was performing hover tests in his experimental helicopter at his private helipad, located 60 feet from his residence. The plt reported winds as variable gusting to 40 knots. The plt's attention was diverted and a wind gust pushed the…
- [NTSB DEN82DA169](https://openairdocs.org/ntsb/DEN82DA169.md): Quicksilver Mxii · Broomfield, CO · Accident · Serious injuries · Final report · Aug 20, 1982 · N3149Z · Substantial damage
  > Reportedly, the pilot made an intersection takeoff from about midfield on runway 02. He stated that he took off at rotation speed plus 2 KTS. The passenger reported that they reached about 40 ft AGL, then lost lift and begun to settle. As the two-place…
- [NTSB DEN82DA165](https://openairdocs.org/ntsb/DEN82DA165.md): Bellanca 7GCBC · Yuma, CO · Accident · No injuries · Final report · Aug 16, 1982 · N5138X · Substantial damage
  > The pilot stated that as he touched down the aircraft porpoised "a couple of times." When the aircraft had slowed to approximately 25-30 mph it ran off the runway into soft dirt and nosed over.
- [NTSB DEN82FTE10](https://openairdocs.org/ntsb/DEN82FTE10.md): Mome II · Longmont, CO · Accident · No injuries · Closed · Nov 23, 1981 · N9993A · Substantial damage

Next page: https://openairdocs.org/ntsb.md?engine=99999&state=CO&page=2

## The whole list in SQL

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

```sql
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" = 'CO' 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 ('99999'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=99999&state=CO

---
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.