# NTSB CEN19LA123: Robinson R66, N766WC, St Jacob, IL, April 21, 2019 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: April 20, 2019, 19:30 local (Apr 21, 2019, 00:30 UTC) - Place: St Jacob, IL - Coordinates: 38.699722, -89.775001 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.6997&lon=-89.7750&mi=10 - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Central Region - Parties: Federal Aviation Administration; STL FSDO - NTSB case key (mKey): 99290 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN19LA123 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/99290/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=99290 - Page: https://openairdocs.org/ntsb/CEN19LA123 ## Probable cause The pilot's in-flight collision with an unmarked wire during an aerial application flight; the wire lacked contrast with the surrounding environment. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Object/animal/substance: wire](https://openairdocs.org/ntsb-findings/03022032): Environmental issues › Physical environment · Ability to respond/compensate (probable cause); cases with it: [Robinson Helicopter R66, 7 cases](https://openairdocs.org/ntsb-findings/03022032/cases.md?model=7640130), [All aircraft, 588 cases](https://openairdocs.org/ntsb-findings/03022032/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Incorrect use/operation (probable cause); cases with it: [Robinson Helicopter R66, 4 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=7640130), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Info processing/decision: identification/recognition](https://openairdocs.org/ntsb-findings/02041510): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Robinson Helicopter R66, 2 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md?model=7640130), [All aircraft, 559 cases](https://openairdocs.org/ntsb-findings/02041510/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: Low altitude operation/event](https://openairdocs.org/ntsb-events/220); cases with it: [Robinson Helicopter R66, 8 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=7640130), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md) - [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240); cases with it: [Robinson Helicopter R66, 5 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=7640130), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Robinson Helicopter R66, 11 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7640130), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot was performing aerial application operations and stated that he aligned the helicopter to perform a pass along the edge of a wheat field. During the pass, he noticed a power line in front of him, but the helicopter was "too close to avoid [it]." He felt the helicopter mast contact the power line; the helicopter began to "shake" violently and then impacted the ground. The pilot stated that he had performed reconnaissance of the field before beginning the application to identify power lines and other obstructions; however, he had not seen the impacted power line during the reconnaissance nor during the application. The pilot stated that there were no mechanical malfunctions or failures of the helicopter. Postaccident examination revealed that the power line was a green copper wire approximately 1/4-inch in diameter. The power line pole at the southern edge of the field was within the tree line and the field vegetation was green; it is likely that this lack of contrast contributed to the pilot's inability to identify the wire. ## Factual narrative On April 20, 2019, at 1930 central daylight time, a Robinson Helicopter Company R66, N766WC, impacted an unmarked powerline and terrain during an aerial application of a field near St Jacob, Illinois. The airline transport pilot received serious injuries and the helicopter sustained substantial damage. The helicopter was registered to and operated by Skyline Helicopters LLC under Title 14 Code of Federal Regulations Part 137 as an aerial application flight that was not operating on a flight plan. Day visual meteorological conditions prevailed at the time of the accident. The local flight originated from St Jacob, Illinois at 1915. The pilot stated the wheat fields, which were not conjoined, were positioned on a north/south orientation; he approached the fields from the south to apply pesticide. When he arrived at the fields, he performed a reconnaissance by flying near their perimeters at about 100-150 feet above ground level to compare their features to those on customer-provided maps of the fields. During the reconnaissance, he identified the northern field to have powerlines/poles that traversed east/west and branched in the middle of the field toward the northwest. He set an east/west A-B line (imaginary reference line set for a field that a tractor/spray guidance system would follow) for the north field and used a back and forth spray pattern that progressed northward. Upon reaching the northern edge of the north field, he set a north/south A-B line for the southern section of the north field and the entire south field, both of which were sprayed simultaneously. The pilot said that his selection of the north/south A-B line was less than ideal for spraying, but it provided better visibility of the powerlines because it avoided direct flight into the sun. He completed the spraying of the north/south A-B lines without incident. He then lined up to perform an eastbound trim pass along the southern-edge of the north field, which had a tree line. The sun was behind him, and he retracted his helmet visor. During the trim pass, he noticed a powerline in front of him, but he was "too close to avoid [it]." He felt the powerline contact the helicopter mast and "shortly" thereafter, the helicopter began to "shake violently" and then impacted the ground. The pilot stated that he had not previously identified the powerline struck by the helicopter, even while flying the north/south spray passes. He said the powerline was oriented north/south and spanned an "abnormally long distance." The powerline spanned from a pole located at the southern edge of the field to a northern pole that was part of the east/west powerline structure. The pilot stated there was no mechanical malfunction/failure of the helicopter. Post-accident examination of the accident site revealed the powerline struck by the helicopter was a copper wire approximately 1/4-inch in diameter and green in color. The powerline pole at the southern edge of the north field was within the tree line,and the field vegetation was green. ## Aircraft - Registration: [N766WC](https://openairdocs.org/deregistered/N766WC-2021-04-03), registration cancelled 2021-04-03, S/N 0397, built 2013 (OpenAirDocs) - Reported make and model: Robinson R66 (No Series) - Registry model: [Robinson Helicopter R66](https://openairdocs.org/model/robinson-helicopter-r66) (registry code 7640130) (OpenAirDocs) - Registry engine: [Rolls-Royce 250-C300/A1](https://openairdocs.org/engine/rolls-royce-250-c300-a1) (registry code 54232, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 0397 - Year built: 2013 - Airframe hours: 724.3 - Engines: Rolls Royce 250-c300/A1 300 horsepower turbo shaft - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Skyline Helicopters LLC - Registered owner: Skyline Helicopters LLC - Airworthiness certificate: Standard, Normal; Special, Restricted (Special) - Last inspection: Annual, January 4, 2019 - Departed: St Jacob, IL - Destination: St Jacob, IL - Equipment: Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 36; injuries: serious; flight instructor, airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: helicopter, airplane; medical: class 1, without waivers/limitations; last flight review April 8, 2019; seat: right; restraint: 3-point; flight hours: 7,176 total, 581 in this make and model, 6,996 as pilot in command, 13 in the last 90 days, 13 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 300° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 68 °F, dew point 37 °F - Altimeter: 29.86 inHg - Observed at: BLV, 10 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 20190420003099A](https://openairdocs.org/incident/20190420003099A), Apr 20, 2019: Robinson Helicopter Co R66, St Jacob, IL, Substantial damage. On April 20, 2019 at approximately 1915 hours, the Robinson R-66 agricultural helicopter sustained substantial damage and the 7000 hour airline transport pilot… ## Docket (2 files) The files NTSB released with the investigation on November 21, 2019, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=99290. 2.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40478269&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Record of Examination (item 2, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40478270&FileExtension=.PDF&FileName=Record%20of%20Examination-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.