# Unknown or undetermined

- Type: NTSB defining event
- NTSB code: 000
- CICTT category: Unknown
- Defining event in: 1,519 cases
- In the sequence of: 1,703 cases
- Fatal cases: 905
- All cases: https://openairdocs.org/ntsb-events/000/cases.md
- Cases with it anywhere in the sequence: https://openairdocs.org/ntsb-events/000/sequence.md
- Page: https://openairdocs.org/ntsb-events/000

## Cases per year (defining / in the sequence)

- 2008: 12 / 17
- 2009: 20 / 31
- 2010: 34 / 52
- 2011: 34 / 44
- 2012: 36 / 47
- 2013: 32 / 43
- 2014: 56 / 65
- 2015: 72 / 82
- 2016: 92 / 100
- 2017: 78 / 83
- 2018: 94 / 98
- 2019: 67 / 82
- 2020: 73 / 87
- 2021: 89 / 95
- 2022: 105 / 124
- 2023: 134 / 152
- 2024: 116 / 122
- 2025: 118 / 120
- 2026: 257 / 259

## Phase of flight

- Unknown: 610 cases
- Enroute: 207 cases
- Initial climb: 116 cases
- Takeoff: 103 cases
- Enroute-cruise: 94 cases
- Maneuvering: 73 cases
- Maneuvering-low-alt flying: 54 cases
- Approach: 50 cases
- Landing: 37 cases
- Other: 22 cases

## In the probable cause of these cases

- [Not determined, general](https://openairdocs.org/ntsb-findings/05000000) (Not determined): 268 cases
- [Engine (reciprocating), general](https://openairdocs.org/ntsb-findings/01058500) (Aircraft): 70 cases
- [Aircraft control](https://openairdocs.org/ntsb-findings/02063040) (Personnel issues): 38 cases
- [Performance/control parameters, general](https://openairdocs.org/ntsb-findings/01062000) (Aircraft): 22 cases
- [Power plant, general](https://openairdocs.org/ntsb-findings/01057100) (Aircraft): 22 cases
- [Decision making/judgment](https://openairdocs.org/ntsb-findings/02041520) (Personnel issues): 17 cases
- [Aircraft power plant, general](https://openairdocs.org/ntsb-findings/01050000) (Aircraft): 16 cases
- [Altitude](https://openairdocs.org/ntsb-findings/01062012) (Aircraft): 14 cases
- [Climb capability](https://openairdocs.org/ntsb-findings/01061010) (Aircraft): 6 cases
- [Directional control](https://openairdocs.org/ntsb-findings/01062020) (Aircraft): 5 cases

## Aircraft models (registry)

- [Cessna 172S](https://openairdocs.org/model/cessna-172s): 12 cases
- [Beech A36](https://openairdocs.org/model/beech-a36): 10 cases
- [Robinson Helicopter R44 II](https://openairdocs.org/model/robinson-helicopter-r44-ii): 8 cases
- [Piper PA-28-140](https://openairdocs.org/model/piper-pa-28-140): 8 cases
- [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150): 8 cases
- [Cirrus Design SR22](https://openairdocs.org/model/cirrus-design-sr22): 8 cases
- [Cessna 172N](https://openairdocs.org/model/cessna-172n): 7 cases
- [Robinson Helicopter R44](https://openairdocs.org/model/robinson-helicopter-r44): 6 cases
- [Piper PA-32-300](https://openairdocs.org/model/piper-pa-32-300): 6 cases
- [Cessna 421C](https://openairdocs.org/model/cessna-421c): 6 cases

## Newest cases

- [NTSB GAA27WA015](https://openairdocs.org/ntsb/GAA27WA015), Oct 16, 2026: Vans RV7 (PP-ZLC), Sao Paulo, Brazil, substantial damage, 2 fatal
- [NTSB GAA27WA013](https://openairdocs.org/ntsb/GAA27WA013), Oct 16, 2026: Piper PA38 (G-LFSU), Dryman, United Kingdom, substantial damage, 2 fatal
- [NTSB GAA27WA014](https://openairdocs.org/ntsb/GAA27WA014), Oct 13, 2026: Champion 7GCAA (HS-FPD), Pattaya, Thailand, destroyed
- [NTSB GAA27WA011](https://openairdocs.org/ntsb/GAA27WA011), Oct 13, 2026: Beech 58 (CX-ISA), San Bernardina, Uruguay, incident
- [NTSB GAA27WA010](https://openairdocs.org/ntsb/GAA27WA010), Oct 11, 2026: Cessna T210 (CC-PCG), Calafquen, Chile, occurrence, substantial damage
- [NTSB GAA27WA008](https://openairdocs.org/ntsb/GAA27WA008), Oct 10, 2026: Cessna 182 (N), Zabaykalsky Krai, Russia
- [NTSB GAA27WA016](https://openairdocs.org/ntsb/GAA27WA016), Oct 9, 2026: Beech 300 (PP-EJO), Santana Do Paraiso, Brazil, 3 fatal
- [NTSB GAA27WA007](https://openairdocs.org/ntsb/GAA27WA007), Oct 9, 2026: Steen Skybolt (C-GLXA), Ontario, Canada, substantial damage
- [NTSB GAA27WA012](https://openairdocs.org/ntsb/GAA27WA012), Oct 8, 2026: Piper PA-25 (HK1083), Villavicencio, Colombia, incident
- [NTSB CEN27FA006](https://openairdocs.org/ntsb/CEN27FA006), Oct 7, 2026: Lancair IV (N5SV), Haslet, TX, destroyed, 1 fatal, investigation ongoing

NTSB has coded findings and defining events since 2008; earlier cases used its older occurrence and cause codes and aren't counted.

Findings: https://openairdocs.org/ntsb-findings.md. Defining events: https://openairdocs.org/ntsb-events.md. Phases of flight: https://openairdocs.org/ntsb-phases.md. Every investigation, filtered by finding, event, phase, state, year or model: https://openairdocs.org/ntsb.md (for example ?state=MI&fatal=1).

NTSB's definitions: Accident and incident, 49 CFR 830.2 (https://www.ecfr.gov/current/title-49/subtitle-B/chapter-VIII/part-830/subpart-A/section-830.2), CICTT occurrence categories (PDF) (https://www.ntsb.gov/safety/data/Documents/datafiles/OccurrenceCategoryDefinitions.pdf), CICTT phases of flight (PDF) (https://www.ntsb.gov/safety/data/Documents/datafiles/PhaseofFlightDefinitions.pdf), and NTSB coding manual, before 2008 (PDF) (https://www.ntsb.gov/GILS/Documents/codman.pdf). NTSB publishes no definitions for its findings, only their names.

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