# NTSB WPR21LA093: Mcdonnell Douglas Helicopter 369E, N90TG, Queen Creek, AZ, January 22, 2021 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: January 22, 2021, 09:30 local (16:30 UTC) - Place: Queen Creek, AZ · Rittenhouse Helicopter Practice Area - Coordinates: 33.32, -111.48 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.3200&lon=-111.4800&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-hover: Loss of tail rotor effectiveness](https://openairdocs.org/ntsb-events/242) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Western Pacific Region - Parties: MD Helicopters, Federal Aviation Administration - NTSB case key (mKey): 102546 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR21LA093 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/102546/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=102546 - Page: https://openairdocs.org/ntsb/WPR21LA093 ## Probable cause The pilot's uncoordinated flight control inputs while entering a hover, which lead to a loss of aircraft control which resulted in the left skid making contact with the ground, causing the helicopter to roll on its side. ## 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: [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Wind: variable wind](https://openairdocs.org/ntsb-findings/03034025): Environmental issues › Conditions/weather/phenomena · Effect on equipment; cases with it: [All aircraft, 113 cases](https://openairdocs.org/ntsb-findings/03034025/cases.md) - [Performance/control parameters: prop/rotor parameters](https://openairdocs.org/ntsb-findings/01062052): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [All aircraft, 182 cases](https://openairdocs.org/ntsb-findings/01062052/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-hover: Loss of tail rotor effectiveness](https://openairdocs.org/ntsb-events/242) (defining event); cases with it: [All aircraft, 100 cases](https://openairdocs.org/ntsb-events/242/sequence.md) ## Analysis The pilot reported that during a practice approach to an off-airport location, he increased the collective and applied left pedal to bring the helicopter to a hover. The helicopter nosed right and continued to rotate as he attempted to stop it by applying left pedal. Subsequently, the helicopter encountered a tail wind situation, and the rate of turn became excessive, as he continued to attempt to arrest the spin. Shortly thereafter, the left skid caught the ground and bent inward, causing the helicopter to roll on its left side. The fuselage and main rotor blades were substantially damaged. The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation. ## Aircraft - Registration: N90TG (not matched to a registry record) - Reported make and model: MCDONNELL DOUGLAS HELICOPTER 369E - Category: Helicopter - Serial number: 383E - Year built: 1990 - Airframe hours: 2411 - Engines: Rolls Royce C20 B 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Peoples Properties LLC - Airworthiness certificate: Standard, Normal - Last inspection: Annual, January 9, 2021 - Departed: SDL, Scottsdala, AZ - Destination: E89, Kearney, AZ - Airport: (AZ38), Rittenhouse Army Heliport - Equipment: ADS-B, Electronic multifunction display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 63; injuries: none; airline transport, flight engineer, commercial, private; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review November 20, 2019; seat: left; restraint: 3-point; flight hours: 20,267 total, 1 in this make and model, 12,357 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 4 knots - Visibility: 10 statute miles - Lowest ceiling: 7,000 ft overcast - Temperature: 55 °F, dew point 48 °F - Altimeter: 30.04 inHg - Observed at: KIWA, 16 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 20210122002339A](https://openairdocs.org/incident/20210122002339A), Jan 22, 2021: Mcdonnell Douglas Helicopter 369E, Queen Creek, AZ, Substantial damage. On 22 January 2021 at around 1630 zulu 0930 MST N90TG, a 1990 Mcdonnell Douglas Helicopter, model 369E serial number 383E, was on approach to Rittenhouse Army… ## Docket (2 files) The files NTSB released with the investigation on September 1, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=102546. 4.5 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 4.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11951981&FileExtension=pdf&FileName=NTSB%20Form%206120_Redacted-Rel.pdf - Accident pictures (item 2, PDF, 1 page, 350 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12614698&FileExtension=pdf&FileName=WPR21LA093%20Pictures%20Final%201-Rel.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.