# Unknown - Type: NTSB phase of flight (CICTT main phase) - CICTT code: 990 - Cases: 1973 - Fatal cases: 1403 - In the older codes (1982 to 2007): 543 - All cases: https://openairdocs.org/ntsb-phases/990/cases.md - Page: https://openairdocs.org/ntsb-phases/990 ## Cases per year (current codes / all) - 1962: 1 / 1 - 1963: 1 / 1 - 1964: 29 / 29 - 1965: 26 / 26 - 1966: 36 / 36 - 1967: 48 / 48 - 1968: 59 / 59 - 1969: 31 / 31 - 1970: 33 / 33 - 1971: 22 / 22 - 1972: 30 / 30 - 1973: 28 / 28 - 1974: 27 / 27 - 1975: 40 / 40 - 1976: 15 / 15 - 1977: 30 / 30 - 1978: 38 / 38 - 1979: 41 / 41 - 1980: 30 / 30 - 1981: 27 / 27 - 1982: 0 / 51 - 1983: 0 / 46 - 1984: 0 / 47 - 1985: 0 / 41 - 1986: 0 / 18 - 1987: 0 / 23 - 1988: 0 / 24 - 1989: 0 / 20 - 1990: 0 / 25 - 1991: 0 / 15 - 1992: 0 / 22 - 1993: 0 / 22 - 1994: 0 / 12 - 1995: 0 / 13 - 1996: 0 / 19 - 1997: 0 / 16 - 1998: 0 / 20 - 1999: 0 / 23 - 2000: 0 / 13 - 2001: 0 / 18 - 2002: 0 / 9 - 2003: 0 / 12 - 2004: 0 / 6 - 2005: 0 / 11 - 2006: 0 / 7 - 2007: 0 / 10 - 2008: 7 / 7 - 2009: 10 / 10 - 2010: 20 / 20 - 2011: 16 / 16 - 2012: 19 / 19 - 2013: 14 / 14 - 2014: 25 / 25 - 2015: 27 / 27 - 2016: 35 / 35 - 2017: 37 / 37 - 2018: 45 / 45 - 2019: 26 / 26 - 2020: 39 / 39 - 2021: 60 / 60 - 2022: 72 / 72 - 2023: 40 / 40 - 2024: 60 / 60 - 2025: 73 / 73 - 2026: 213 / 213 ## CICTT sub-phases (1962 to 1981, 2008 on) - Unknown (990): 1,430 cases ## Older codes counted here (1982 to 2007) - Unknown (610): 543 cases ## Defining events in this phase (2008 on) - [Unknown or undetermined](https://openairdocs.org/ntsb-events/000): 610 cases - [Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470): 48 cases - [Loss of control in flight](https://openairdocs.org/ntsb-events/240): 33 cases - [Loss of engine power (total)](https://openairdocs.org/ntsb-events/341): 23 cases - [Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120): 18 cases - [Missing aircraft](https://openairdocs.org/ntsb-events/990): 13 cases - [Miscellaneous/other](https://openairdocs.org/ntsb-events/900): 10 cases - [Midair collision](https://openairdocs.org/ntsb-events/250): 9 cases - [Collision during takeoff/land](https://openairdocs.org/ntsb-events/490): 7 cases - [Fire/smoke (non-impact)](https://openairdocs.org/ntsb-events/150): 7 cases ## In the probable cause (2008 on) - [Not determined, general](https://openairdocs.org/ntsb-findings/05000000): 105 cases - [Aircraft control](https://openairdocs.org/ntsb-findings/02063040): 15 cases - [Decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): 7 cases - [Performance/control parameters, general](https://openairdocs.org/ntsb-findings/01062000): 7 cases - [Engine (reciprocating), general](https://openairdocs.org/ntsb-findings/01058500): 5 cases - [Airspeed](https://openairdocs.org/ntsb-findings/01062010): 4 cases - [Directional control](https://openairdocs.org/ntsb-findings/01062020): 3 cases - [Stolen/unauthorized](https://openairdocs.org/ntsb-findings/02051020): 2 cases - [Incomplete action](https://openairdocs.org/ntsb-findings/02041040): 2 cases - [Incorrect action selection](https://openairdocs.org/ntsb-findings/02041010): 2 cases ## Aircraft models (registry, all years) - [Piper PA-23-250](https://openairdocs.org/model/piper-pa-23-250): 27 cases - [Piper PA-28-140](https://openairdocs.org/model/piper-pa-28-140): 22 cases - [Cessna 172N](https://openairdocs.org/model/cessna-172n): 18 cases - [Cessna 152](https://openairdocs.org/model/cessna-152): 18 cases - [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150): 16 cases - [Cessna 172M](https://openairdocs.org/model/cessna-172m): 16 cases - [Piper PA-24-250](https://openairdocs.org/model/piper-pa-24-250): 14 cases - [Piper J3C-65](https://openairdocs.org/model/piper-j3c-65): 14 cases - [Piper PA-28-180](https://openairdocs.org/model/piper-pa-28-180): 12 cases - [Piper PA-30](https://openairdocs.org/model/piper-pa-30): 12 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 GAA27WA003](https://openairdocs.org/ntsb/GAA27WA003), Oct 6, 2026: Rutan Varieze (G-BIMX), Worplesdon, United Kingdom, substantial damage, 1 fatal From 1962 to 1981 and from 2008 on, NTSB codes phases with the CICTT phases; from 1982 to 2007 with its older phase codes, counted under the CICTT main phase each maps to. Each case counts once, on its first aircraft: by its defining event's phase from 2008, its first event's before 1982, and its first occurrence's from 1982 to 2007. Compare years within an era: a first occurrence (1982 to 2007) is often in flight, before the landing, so landings count lower then. 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. --- 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.