# NTSB ERA22LA229: Messerschmitt-Bolkow-Blohm BK 117 B-2, N370SS, Rochester, NY, May 14, 2022 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: May 13, 2022, 21:00 local (May 14, 2022, 01:00 UTC) - Place: Rochester, NY - Coordinates: 43.123253, -77.624122 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.1233&lon=-77.6241&mi=10 - Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping) - Defining event: [Standing-engine(s) operating: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: German Federal Bureau of Aircraft Accident Investigation, Airbus Helicopters, FAA/FSDO - NTSB case key (mKey): 105085 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA22LA229 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/105085/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=105085 - Page: https://openairdocs.org/ntsb/ERA22LA229 ## Probable cause An unintentional movement of the cyclic control before takeoff, which resulted the main rotor blades contacting the fixed wire cutter. ## 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: [Messerschmitt-Bolkow-Blohm BK 117 B-2, 2 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=5626013), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Messerschmitt-Bolkow-Blohm BK 117 B-2, 1 case](https://openairdocs.org/ntsb-findings/02041015/cases.md?model=5626013), [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) - [Performance/control parameters](https://openairdocs.org/ntsb-findings/01062000): Aircraft › Aircraft oper/perf/capability · Incorrect use/operation (probable cause); cases with it: [Messerschmitt-Bolkow-Blohm BK 117 B-2, 1 case](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=5626013), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/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: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) (defining event); cases with it: [Messerschmitt-Bolkow-Blohm BK 117 B-2, 3 cases](https://openairdocs.org/ntsb-events/900/sequence.md?model=5626013), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) ## Analysis After the pilot of the air medical helicopter landed, the medical crew boarded and he prepared the helicopter for takeoff. The pilot stated that he was adjusting a light switch while his right hand was on the cyclic control when he heard a loud “bang.” He subsequently noticed that the rod from the airframe-mounted wire cutter was bouncing back and forth. The pilot then shut down the engines and the crew exited the helicopter. A postaccident examination of the helicopter revealed substantial damage to the main rotor blades that was consistent with them having contacted the wire cutter. The examinations otherwise did not reveal evidence of any anomalies of the flight control system that would have precluded normal operation. Based on this information, while the pilot indicated that he was holding the cyclic control at the time of the event, given the damage to the helicopter and the lack of anomalous findings with the flight control system, nor the existence other external influences like substantive wind, it is likely that he inadvertently moved the cyclic, which resulted in the main rotor briefly moving into a position where it contacted the wire cutter. ## Factual narrative On May 13, 2022, about 2100 eastern daylight time, a Messerschmitt-Bolkow-Blohm BK117 B-2 helicopter, N370SS, was substantially damaged when it was involved in an accident at the Strong Memorial Hospital Heliport, Rochester, New York. The commercial pilot and two crewmembers were not injured. The helicopter was operated as a Title 14 Code of Federal Regulations Part 135 air ambulance flight. The pilot reported that he landed on the helipad and moved his left hand from the collective to the power levers. He said the crew was ready to go and entered the helicopter shortly after landing. Once the crew entered the helicopter and “buckled in,” the pilot moved the power levers to “fly,” turned the light switches on, and began to move the “Hat” to adjust the lights on the rooftop. The pilot stated that his right hand was in control of the cyclic when he heard a loud “bang” and noticed the rod from the wire cutter bouncing back and forth. The pilot immediately shut down the engines and the crew exited the helicopter. The pilot reported that the wind was light and variable at a velocity of about 3 mph at the time of the accident. Examination of the helicopter by a Federal Aviation Administration inspector revealed damage to the main rotor blades and the wire cutter. A rigging check of the flight controls was performed under the supervision of an FAA inspector, and no anomalies were noted that would have contributed accident. A static functional test of the mast moment indicator was performed, with no anomalies noted. A pre-departure test run was also performed with no anomalies. A review of the last 12-month and 100-hour maintenance inspections did not reveal evidence of any relevant maintenance to any of the helicopter’s flight control systems ## Aircraft - Registration: [N370SS](https://openairdocs.org/deregistered/N370SS-2023-10-31), registration cancelled 2023-10-31, S/N 7133, built 1987 (OpenAirDocs) - Reported make and model: MESSERSCHMITT-BOLKOW-BLOHM BK 117 B-2 - Registry model: [Messerschmitt-Bolkow-Blohm BK 117 B-2](https://openairdocs.org/model/messerschmitt-bolkow-blohm-bk-117-b-2) (registry code 5626013) (OpenAirDocs) - Registry engine: [Honeywell LTS101-750B-1](https://openairdocs.org/engine/honeywell-lts101-750b-1) (registry code 33826, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 7133 - Year built: 1987 - Airframe hours: 16702 - Engines: Lycoming LTS101-750B1 700 horsepower turbo shaft; Lycoming LTS101-750B1 700 horsepower turbo shaft - Damage: Substantial damage - Flight: Part 135 - Operator: Mercy Flight Central - Registered owner: Mercy Flight Central - Airworthiness certificate: Standard, Transport; Standard, Normal - Last inspection: Annual, March 21, 2022, 641 hours before - Flight plan: Company VFR - Airport: 2NY5, Strong Memorial Hospital Heliport, runway H1, 48 × 48 ft - Equipment: Electronic flight bag or handheld device, ADS-B, Satellite tracking device ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; injuries: none; commercial; instrument ratings: helicopter; medical: class 2, with waivers/limitations; last flight review February 18, 2022; seat: right; restraint: 4-point; flight hours: 3,358 total, 28 in this make and model, 3,278 as pilot in command, 28 in the last 90 days, 8 in the last 30 days - Cabin crew; injuries: none; seat: left; restraint: 4-point - Cabin crew; injuries: none; seat: rear; restraint: 4-point ## Weather - Conditions: Visual (VMC), Dusk - Wind: variable at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 78 °F, dew point 57 °F - Altimeter: 29.74 inHg - Observed at: ROC, 2 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 20220513006899A](https://openairdocs.org/incident/20220513006899A), May 13, 2022: Messerschmitt-Bolkow-Blohm BK 117 B-2, Rochester, NY, Substantial damage. At 11:45 am inspectors arrived at strong hospital main desk and was directed to the emergency room. From there, an escort was given to the helo pad by hospital… ## Docket (6 files) The files NTSB released with the investigation on March 20, 2024, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=105085. 71.6 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 2.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14552546&FileExtension=pdf&FileName=6120%20LA229_Redacted-Rel.pdf - Memorandum for record - FAA inspector interview (item 2, PDF, 1 page, 128 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14552120&FileExtension=pdf&FileName=Memorandum%20for%20Record%20FAA%20damage%20assessment%20LA229-Rel.pdf - FAA rigging examination summary (item 3, PDF, 1 page, 85 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16576355&FileExtension=pdf&FileName=MFR%20LA229%20Rigging%20notes-Rel.pdf - BK117 flight manual excerpts (item 4, PDF, 4 pages, 345 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14553215&FileExtension=pdf&FileName=BK117%20Flight%20Manual%20excerpts-Rel.pdf - Maintenance records (item 5, PDF, 3 pages, 68.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14552302&FileExtension=pdf&FileName=MX%20record%20excerpts%20LA229_Redacted-Rel.pdf - Investigative photos (item 6, PDF, 3 pages, 261 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14553650&FileExtension=pdf&FileName=Investigative%20Photos%20%20LA229-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.