# NTSB CEN16LA284: Texas Helicopter OH 13H/M74A, N10009, Minonk, IL, July 25, 2016 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 25, 2016, 10:50 local (15:50 UTC) - Place: Minonk, IL - Coordinates: 40.832778, -88.968887 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.8328&lon=-88.9689&mi=10 - Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping) - Defining event: [Standing-engine(s) operating: Ground collision](https://openairdocs.org/ntsb-events/200) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report June 25, 2019 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA Springfield FSDO - NTSB case key (mKey): 93681 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN16LA284 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/93681/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=93681 - Page: https://openairdocs.org/ntsb/CEN16LA284 ## Probable cause Failure of the truck driver to ensure that he had adequate clearance to pass under the helicopter and the failure of the loader to park in a safer area for reloading operations. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Planning/preparation](https://openairdocs.org/ntsb-findings/02061000): Personnel issues › Task performance · Ground crew (probable cause); cases with it: [Texas Helicopter OH-13H/M74A, 1 case](https://openairdocs.org/ntsb-findings/02061000/cases.md?model=8930105), [All aircraft, 113 cases](https://openairdocs.org/ntsb-findings/02061000/cases.md) - [Personnel issues](https://openairdocs.org/ntsb-findings/02060000): Personnel issues › Task performance · Other (probable cause); cases with it: [Texas Helicopter OH-13H/M74A, 1 case](https://openairdocs.org/ntsb-findings/02060000/cases.md?model=8930105), [All aircraft, 137 cases](https://openairdocs.org/ntsb-findings/02060000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Standing-engine(s) operating: Aircraft loading event](https://openairdocs.org/ntsb-events/010); cases with it: [Texas Helicopter OH-13H/M74A, 1 case](https://openairdocs.org/ntsb-events/010/sequence.md?model=8930105), [All aircraft, 84 cases](https://openairdocs.org/ntsb-events/010/sequence.md) - [Standing-engine(s) operating: Ground collision](https://openairdocs.org/ntsb-events/200) (defining event); cases with it: [Texas Helicopter OH-13H/M74A, 1 case](https://openairdocs.org/ntsb-events/200/sequence.md?model=8930105), [All aircraft, 618 cases](https://openairdocs.org/ntsb-events/200/sequence.md) ## Analysis During reloading operations for an agricultural flight, the nurse truck was parked on the right shoulder of a road, facing west. The helicopter was parked on the elevated helipad on top of the nurse truck, facing north, with the engine running and rotor blades turning. The helicopter's tail boom and rotor disk extended about 8-10 ft over the road. As the loader was reloading the helicopter's product tanks, a westbound semi-trailer truck drove underneath the rotor disk and struck the helicopter's tail boom. The semi-trailer truck driver said he thought he had enough clearance to pass safely under the helicopter's tail rotor. The pilot said that if the nurse truck had parked closer to an adjoining field, the platform would have a tilt, making it difficult to land for servicing. It is likely that the semi-trailer truck driver failed to ensure that he had adequate clearance to pass under the helicopter and that the loader failed to park in a safer area for the reloading operations. ## Factual narrative On July 25, 2016, about 1050 central daylight time, a Texas Helicopter OH-13H/M74A, N10009, was substantially damaged when it was struck by a passing semi-trailer truck during reloading operations near Minonk, Illinois. The pilot, loader, and truck driver were not injured. The helicopter was registered to and operated by Hendrickson Flying Service, Rochelle, Illinois, under the provisions of Title 14 Code of Federal Regulations Part 137 as an agricultural application flight. Visual meteorological conditions prevailed, and no flight plan for the local flight had been filed.The agricultural application nurse truck was stationary and parked on the right shoulder of a paved rural county road, facing west, and was completely clear of the roadway surface. According to the loader, the nurse truck's hazard lights were on. The helicopter was parked on the elevated helipad on top of the nurse truck with the helicopter's engine operating and the rotor blades turning. The nose of the helicopter faced north, and the helicopter's tail boom and rotor disk extended about 8-10 feet over the road. The loader stated that he was reloading the helicopter's product tanks when a westbound semi-trailer truck drove underneath the rotor disk and struck the helicopter's tail boom. The impact turned the helicopter 20-30° from its position on the helipad. The helicopter remained upright and on the top of the helipad. The right side of the cab and the cargo cover and frame to the truck trailer were damaged. The truck driver told a Federal Aviation Administration (FAA) inspector that he thought he had enough clearance to pass safely under the helicopter's tail rotor. He maintained that the accident was not his fault. The pilot was asked why the truck was positioned so that the helicopter's tail boom was extended 10 feet over the highway. He replied that if he had parked closer to an adjoining field, the platform would have a tilt, making it difficult to land for servicing. The loader provided a statement and said that, in the future, if loading operations need to occur off a well-traveled road, they would take measures to ensure the tail boom is not over the main road. After examining the accident site, the inspector noted that were other flat areas in the vicinity but considered too far from the field being sprayed. The inspector also noted that the tilt would not have been significant or impeded the highway. ## Aircraft - Registration: [N10009](https://openairdocs.org/aircraft/N10009), registered now, S/N 79-032, built 1979 (OpenAirDocs) - Reported make and model: TEXAS HELICOPTER CORP OH 13H/M74A - Registry model: [Texas Helicopter OH-13H/M74A](https://openairdocs.org/model/texas-helicopter-oh-13h-m74a) (registry code 8930105) (OpenAirDocs) - Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 79-032 - Year built: 1979 - Engines: LYCOMING VO-435 A1F 200 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Hendrickson Flying Service Inc, doing business as Hendrickson Flying Service - Registered owner: Hendrickson Flying Service Inc - Airworthiness certificate: Special, Restricted (Special) - Departed: NONE, Minook, IL - Destination: NONE, Minook, IL ## Weather - Conditions: Visual (VMC), Day - Wind: 330° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 79 °F, dew point 73 °F - Altimeter: 30.02 inHg - Observed at: KPNT, 17 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 20160725011569A](https://openairdocs.org/incident/20160725011569A), Jul 25, 2016: Texas Helicopter Corp OH-13H/M74A, Minonk, IL, Substantial damage. On July 25, 2016, approximately 1050 local time, a Texas Helicopter Corp OH-13H/M74A, N10009, was Substantially damaged during loading operations near Minonk,… ## Other investigations on N10009 (3) 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. - [NTSB CEN13LA442](https://openairdocs.org/ntsb/CEN13LA442), Jul 29, 2013: Texas Helicopter OH-13H/M74A (N10009), Streator, IL, substantial damage. Probable cause: The pilot's diverted attention during an agricultural application maneuver, which resulted in the helicopter impacting a corn field. - [NTSB CEN11CA524](https://openairdocs.org/ntsb/CEN11CA524), Jul 28, 2011: Texas Helicopter OH-13H/M74A (N10009), Creston, IL, substantial damage. Probable cause: The pilot's failure to maintain adequate skid clearance from the helicopter cart during landing, resulting in a dynamic rollover. - [NTSB CHI04CA180](https://openairdocs.org/ntsb/CHI04CA180), Jul 9, 2004: Texas Helicopter M-74 (N10009), Clear Lake, MN, substantial damage. Probable cause: The pilot failed to maintain a proper glidepath to the landing zone. A factor was the truck pad. ## Docket (6 files) The files NTSB released with the investigation on March 24, 2019, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=93681. 1.1 MB in all. - E-Mail from FAA Inspector (item 1, .PDF, 176 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40464106&FileExtension=.PDF&FileName=E-Mail%20from%20FAA%20Inspector-Master.PDF - Chicago Sectional Chart Excerpt (item 2, .PDF, 407 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40464107&FileExtension=.PDF&FileName=Chicago%20Sectional%20Chart%20Excerpt-Master.PDF - Chart (Provided by Operator) (item 3, .PDF, 104 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40464108&FileExtension=.PDF&FileName=Chart%20(Provided%20by%20Operator)-Master.PDF - AgSync Work Order (item 4, .PDF, 252 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40464109&FileExtension=.PDF&FileName=AgSync%20Work%20Order-Master.PDF - Witness Statements (item 5, .PDF, 69 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40472453&FileExtension=.PDF&FileName=Witness%20Statements-Master.PDF - Revised Factual Narrative (item 6, .PDF, 50 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40472602&FileExtension=.PDF&FileName=Revised%20Factual%20Narrative-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.