# NTSB CEN12LA443: Robinson Helicopter R44 II, N556MM, Red Oak, IA, July 14, 2012 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 14, 2012, 17:50 local (22:50 UTC) - Place: Red Oak, IA - Coordinates: 41.086112, -95.263053 - Nearby events: https://openairdocs.org/map.md?lat=41.0861&lon=-95.2631&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-flare/touchdown: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report October 9, 2012 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - Des Moines FSDO - NTSB case key (mKey): 84323 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN12LA443 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/84323/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=84323 - Page: https://openairdocs.org/ntsb/CEN12LA443 ## Probable cause The pilot's failure to maintain clearance from the ground-support vehicle during landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Object/animal/substance: ground vehicle](https://openairdocs.org/ntsb-findings/03022025): Environmental issues › Physical environment · Response/compensation (probable cause); cases with it: [Robinson Helicopter R44 II, 4 cases](https://openairdocs.org/ntsb-findings/03022025/cases.md?model=7640122), [All aircraft, 132 cases](https://openairdocs.org/ntsb-findings/03022025/cases.md) - [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Robinson Helicopter R44 II, 29 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=7640122), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-flare/touchdown: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) (defining event); cases with it: [Robinson Helicopter R44 II, 16 cases](https://openairdocs.org/ntsb-events/490/sequence.md?model=7640122), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md) ## Analysis The pilot reported that he was unable to activate the motorized spray system after arriving at the field to be sprayed. He returned to the departure location in order to troubleshoot the inoperative spray system. As he maneuvered the helicopter to land next to a ground-support vehicle, the main rotor system impacted a landing platform installed on top of the vehicle. The pilot reported that there were no preimpact mechanical malfunctions or failures that would have precluded normal operation of the helicopter. The wind near the time of the accident was reported as calm. In the absence of any mechanical malfunctions or adverse atmospheric conditions, the pilot should have been able to maintain proper distance from the known obstacle. ## Factual narrative On July 14, 2012, at 1750 central daylight time, a Robinson Helicopter Company model R44 II, N556MM, was substantially damaged when it impacted a ground-support vehicle while landing near Red Oak, Iowa. The commercial pilot was not injured. The helicopter was registered to and operated by Johnson Helicopter Services LLC, under the provisions of 14 Code of Federal Regulations Part 137 without a flight plan. Day visual meteorological conditions prevailed for the local aerial-application flight that originated from an agricultural field near Red Oak, Iowa, about 1745. The pilot reported that after takeoff he was unable to activate the motorized spray system after arriving at the field to be sprayed. He returned to the departure location in order to troubleshoot the inoperative spray system. As he maneuvered the helicopter to land next to a ground-support vehicle, the main rotor system impacted a landing platform installed on top of the vehicle. The pilot reported that after the impact there was a vibration throughout the helicopter and elevated cyclic stick pressures. The main rotor system, tail boom, and fuselage were damaged during the accident sequence. The pilot reported that there were no preimpact mechanical malfunctions or failures that would have precluded normal operation of the helicopter. The closest weather observing station was at Red Oak Municipal Airport (KRDK), located about 5 miles south of the accident site. At 1755, the KRDK automated surface observing system reported the following weather conditions: calm wind, visibility 10 miles, temperature 33 degrees Celsius, dew point 22 degrees Celsius, altimeter setting 29.97 inches of mercury. The sky condition was not reported. ## Aircraft - Registration: [N556MM](https://openairdocs.org/deregistered/N556MM-2017-10-20), registration cancelled 2017-10-20, S/N 10111, built 2003 (OpenAirDocs) - Reported make and model: Robinson Helicopter Company R44 II - Registry model: [Robinson Helicopter R44 II](https://openairdocs.org/model/robinson-helicopter-r44-ii) (registry code 7640122) (OpenAirDocs) - Registry engine: [Lycoming IO-540 series](https://openairdocs.org/engine/lycoming-io-540-series) (registry code 41530, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 10111 - Airframe hours: 910 - Engines: Lycoming IO-540-AE1A5 245 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Johnson Helicopter Services, LLC. - Registered owner: Johnson Helicopter Services, LLC. - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, July 3, 2012 - Departed: Red Oak, IA - Destination: Red Oak, IA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; injuries: none; commercial, flight instructor; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review June 17, 2011; seat: right; flight hours: 1,327 total, 562 in this make and model, 1,247 as pilot in command, 100 in the last 90 days, 87 in the last 30 days, 14 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 91 °F, dew point 72 °F - Altimeter: 29.96 inHg - Observed at: KRDK, 5 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 20120714015549A](https://openairdocs.org/incident/20120714015549A), Jul 14, 2012: Robinson Helicopter Company R44 II, Red Oak, IA, Destroyed. The airman departed an agricultural field site after servicing the aircraft with chemicals for aerial application. While flying away the airman noted that the… ## Docket (5 files) The files NTSB released with the investigation on August 22, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=84323. 1.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 738 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40375618&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - FAA Inspector Statement (item 2, .PDF, 111 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40375619&FileExtension=.PDF&FileName=FAA%20Inspector%20Statement-Redacted.PDF - Weather Reports (item 3, .PDF, 121 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40375620&FileExtension=.PDF&FileName=Weather%20Reports-Master.PDF - Photo 01 - Main Wreckage Overview (item 4, .PDF, 287 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40375621&FileExtension=.PDF&FileName=Photo%2001%20-%20Main%20Wreckage%20Overview-Master.PDF - Photo 02 - Main Wreckage Overview (item 5, .PDF, 268 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40375622&FileExtension=.PDF&FileName=Photo%2002%20-%20Main%20Wreckage%20Overview-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.