# NTSB GAA16CA372: Bell OH 58, N588MP, Surprise, AZ, July 10, 2016 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: July 10, 2016, 12:30 local (19:30 UTC) - Place: Surprise, AZ - Coordinates: 33.579166, -112.415275 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.5792&lon=-112.4153&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report August 31, 2016 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 93597 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA16CA372 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/93597/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=93597 - Page: https://openairdocs.org/ntsb/GAA16CA372 ## Probable cause While at a low altitude, the pilot's decision to do an abrupt descending right downwind turn which resulted in flying through his own vortices and an impact with terrain. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Bell OH-58A, 12 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=1181579), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Bell OH-58A, 4 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=1181579), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Turbulence: wake turbulence](https://openairdocs.org/ntsb-findings/03032025): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Bell OH-58A, 1 case](https://openairdocs.org/ntsb-findings/03032025/cases.md?model=1181579), [All aircraft, 47 cases](https://openairdocs.org/ntsb-findings/03032025/cases.md) - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Bell OH-58A, 4 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=1181579), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Aircraft wake turb encounter](https://openairdocs.org/ntsb-events/361); cases with it: [Bell OH-58A, 1 case](https://openairdocs.org/ntsb-events/361/sequence.md?model=1181579), [All aircraft, 37 cases](https://openairdocs.org/ntsb-events/361/sequence.md) - [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Bell OH-58A, 6 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=1181579), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Maneuvering-low-alt flying: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Bell OH-58A, 12 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1181579), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot of an aerial application helicopter reported that after spraying a field he noticed that he missed a portion of the field. The pilot further reported that he maneuvered at a low altitude to the south end of the field, made a quick right turn to the north, dove into the field at approximately 45 knots, flew into his own vortices, and impacted the terrain. The helicopter sustained substantial damage to the fuselage. The pilot reported that there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. ## Factual narrative The pilot of an aerial application helicopter reported that after spraying a field he noticed that he missed a portion of the field. The pilot further reported that he maneuvered at a low altitude to the south end of the field, made a quick right turn to the north, dove into the field at approximately 45 knots, flew into his own vortices, and impacted the terrain. The helicopter sustained substantial damage to the fuselage. The pilot reported that there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. ## Aircraft - Registration: [N588MP](https://openairdocs.org/aircraft/N588MP), registered now, S/N 72-21432, built 1972 (OpenAirDocs) - Reported make and model: BELL OH 58 (A) - Registry model: [Bell OH-58A](https://openairdocs.org/model/bell-oh-58a) (registry code 1181579) (OpenAirDocs) - Registry engine: [Allison T63 series](https://openairdocs.org/engine/allison-t63-series) (registry code 03031, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 72-21432 - Year built: 1972 - Airframe hours: 10029 - Engines: ALLISON 250-C20 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Aerial application, Part 137 - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, April 5, 2016 - Departed: Buckeye, AZ - Destination: Buckeye, AZ - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 45; injuries: minor; flight instructor, commercial; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review April 11, 2016; seat: right; restraint: lap only; flight hours: 2,301.1 total, 800 in this make and model, 2,180.1 as pilot in command, 114.8 in the last 90 days, 23.3 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 10 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 104 °F, dew point 41 °F - Altimeter: 29.80 inHg - Observed at: KLUF, 3 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20160710011929A](https://openairdocs.org/incident/20160710011929A), Jul 10, 2016: Bell OH-58A, Surprise, AZ, Substantial damage. At approximately 1210 MST, the commercial pilot had been at work approximately three and one half hours before the accident. The pilot stated he had finished… ## Docket (4 files) The files NTSB released with the investigation on August 9, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=93597. 1.7 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 882 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40443004&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Memorandum for Record - Telephone Interview, Pilot (item 2, .PDF, 123 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40443006&FileExtension=.PDF&FileName=Memorandum%20for%20Record%20-%20Telephone%20Interview,%20Pilot-Master.PDF - Email Exchange, Pilot (item 3, .PDF, 99 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40443007&FileExtension=.PDF&FileName=Email%20Exchange,%20Pilot-Master.PDF - Accident Photo (Courtesy of FAA) (item 4, .PDF, 1 photo, 586 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40443005&FileExtension=.PDF&FileName=Accident%20Photo%20(Courtesy%20of%20FAA)-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- 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.