# Prop/rotor parameters - Type: NTSB finding subsection - Path: [Aircraft](https://openairdocs.org/ntsb-findings/01) › [Aircraft oper/perf/capability](https://openairdocs.org/ntsb-findings/0106) › [Performance/control parameters](https://openairdocs.org/ntsb-findings/010620) › Prop/rotor parameters - NTSB code: 01062052 - Cases: 182 - In the probable cause: 173 - Fatal cases: 20 - All cases: https://openairdocs.org/ntsb-findings/01062052/cases.md - Cases with it in the probable cause: https://openairdocs.org/ntsb-findings/01062052/cases.md?cause=1 - Page: https://openairdocs.org/ntsb-findings/01062052 ## Cases per year (in the probable cause / all) - 2008: 15 / 15 - 2009: 15 / 17 - 2010: 8 / 8 - 2011: 8 / 9 - 2012: 16 / 16 - 2013: 15 / 15 - 2014: 12 / 12 - 2015: 14 / 15 - 2016: 12 / 13 - 2017: 16 / 16 - 2018: 11 / 12 - 2019: 9 / 9 - 2020: 4 / 4 - 2021: 4 / 5 - 2022: 2 / 2 - 2023: 5 / 6 - 2024: 3 / 4 - 2025: 2 / 2 - 2026: 2 / 2 ## Defining events in these cases - [Loss of control in flight](https://openairdocs.org/ntsb-events/240): 52 cases - [Hard landing](https://openairdocs.org/ntsb-events/092): 36 cases - [Loss of tail rotor effectiveness](https://openairdocs.org/ntsb-events/242): 25 cases - [Miscellaneous/other](https://openairdocs.org/ntsb-events/900): 11 cases - [Loss of lift](https://openairdocs.org/ntsb-events/500): 9 cases - [Low altitude operation/event](https://openairdocs.org/ntsb-events/220): 8 cases - [Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342): 5 cases - [Settling with power/vortex ring state](https://openairdocs.org/ntsb-events/244): 5 cases - [Loss of engine power (total)](https://openairdocs.org/ntsb-events/341): 4 cases - [Flight control sys malf/fail](https://openairdocs.org/ntsb-events/333): 3 cases ## Aircraft models (registry) - [Robinson Helicopter R22 BETA](https://openairdocs.org/model/robinson-helicopter-r22-beta): 37 cases - [Robinson Helicopter R44 II](https://openairdocs.org/model/robinson-helicopter-r44-ii): 17 cases - [Robinson Helicopter R44](https://openairdocs.org/model/robinson-helicopter-r44): 15 cases - [Bell 206B](https://openairdocs.org/model/bell-206b): 11 cases - [Hughes 269A](https://openairdocs.org/model/hughes-269a): 7 cases - [Schweizer 269C](https://openairdocs.org/model/schweizer-269c): 5 cases - [Robinson Helicopter R22](https://openairdocs.org/model/robinson-helicopter-r22): 4 cases - [Enstrom F-28C](https://openairdocs.org/model/enstrom-f-28c): 3 cases - [Bell 407](https://openairdocs.org/model/bell-407): 3 cases - [Helicopteres Guimbal CABRI G2](https://openairdocs.org/model/helicopteres-guimbal-cabri-g2): 2 cases ## Other findings in the same cases - [Aircraft control](https://openairdocs.org/ntsb-findings/02063040) (Personnel issues): 106 cases - [Delayed action](https://openairdocs.org/ntsb-findings/02041025) (Personnel issues): 32 cases - [Use of equip/system](https://openairdocs.org/ntsb-findings/02063015) (Personnel issues): 28 cases - [Incorrect action performance](https://openairdocs.org/ntsb-findings/02041015) (Personnel issues): 18 cases - [Gusts](https://openairdocs.org/ntsb-findings/03034045) (Environmental issues): 14 cases - [Tailwind](https://openairdocs.org/ntsb-findings/03034015) (Environmental issues): 14 cases - [Decision making/judgment](https://openairdocs.org/ntsb-findings/02041520) (Personnel issues): 14 cases - [Monitoring other person](https://openairdocs.org/ntsb-findings/02021535) (Personnel issues): 14 cases - [High density altitude](https://openairdocs.org/ntsb-findings/03031020) (Environmental issues): 11 cases - [Descent rate](https://openairdocs.org/ntsb-findings/01062037) (Aircraft): 9 cases ## Newest cases - [NTSB CEN26LA168](https://openairdocs.org/ntsb/CEN26LA168), Apr 17, 2026: Robinson Helicopter R44 (N445JS), Mount Blanco, TX, substantial damage. Probable cause: The pilot’s failure to maintain proper main rotor rpm during a low-level turn, which resulted in the main rotor rpm drooping, a loss of control at an altitude too low for recovery, and a subsequent… - [NTSB ERA26LA119](https://openairdocs.org/ntsb/ERA26LA119), Feb 17, 2026: Tabor W Coates AR-1 (N220SM), Kissimmee, FL, substantial damage. Probable cause: The pilot’s failure to obtain the proper rotor rpm during the takeoff roll which resulted in a loss of control. - [NTSB CEN25LA380](https://openairdocs.org/ntsb/CEN25LA380), Sep 16, 2025: Bell 407 (N407WA), Decatur, TX, substantial damage. Probable cause: The instructor candidate’s erroneous operation of the throttle during an autorotation from altitude with power recovery, which resulted in a hard landing. - [NTSB ERA25LA237](https://openairdocs.org/ntsb/ERA25LA237), Jun 23, 2025: Gyro Technic GT-VX2 (N62XF), Swanzey, NH, substantial damage. Probable cause: The pilot’s failure to maintain rotor rpm of the gyroplane during a low approach, while distracted by other aircraft in the airport traffic pattern, which resulted in the pilot’s decision to perform… - [NTSB WPR24LA262](https://openairdocs.org/ntsb/WPR24LA262), Jul 24, 2024: Hiller UH-12E (N3375T), Bonners Ferry, ID, substantial damage. Probable cause: The pilot’s improper selection of a landing site, which resulted in a main rotor strike. Contributing to the accident was the pilot’s improper performance planning and altitude selection over water,… - [NTSB CEN24FA248](https://openairdocs.org/ntsb/CEN24FA248), Jul 5, 2024: Rotorway Scorpion 133 (N51017), Andale, KS, destroyed, 1 fatal. Probable cause: The pilot’s abrupt control inputs, which resulted in a low-G condition, main rotor mast bumping, and subsequent severing of the tailboom by the main rotor blades. - [NTSB WPR24FA200](https://openairdocs.org/ntsb/WPR24FA200), Jun 19, 2024: Robinson Helicopter R44 II (N323TT), Bluestem, WA, destroyed, 2 fatal. Probable cause: The pilot’s failure to manage main rotor rpm during an autorotation, which resulted in a loss of helicopter control. Contributing to the accident was a loss of power for reasons that could not be… - [NTSB ANC24LA039](https://openairdocs.org/ntsb/ANC24LA039), May 30, 2024: Robinson Helicopter R22 Beta (N333PJ), Kailua-Kona, HI, substantial damage. Probable cause: The flight instructor’s failure to implement the correct action for low rotor RPM recovery. - [NTSB CEN24LA013](https://openairdocs.org/ntsb/CEN24LA013), Oct 16, 2023: Magni M24 (N90HM), Mount Sterling, IL, substantial damage. Probable cause: The pilot’s failure to maintain gyroplane control on the downwind leg, which resulted in impact with terrain. Contributing to the accident was the pilot’s distraction. - [NTSB CEN23LA389](https://openairdocs.org/ntsb/CEN23LA389), Aug 31, 2023: Mcdonnell Douglas Heli 530FF (N530JR), Liberty Hill, TX, substantial damage. Probable cause: The pilot’s improper recovery from a practice autorotation resulting in a hard landing. Contributing to the accident was the instructor’s inadequate supervision of the pilot receiving instruction. 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. --- 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.