# NTSB CEN21LA128: Agustawestland Philadelphia AW119MKII, N352LL, Alexandria, MN, February 13, 2021 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: February 13, 2021, 11:11 local (17:11 UTC) - Place: Alexandria, MN - Coordinates: 45.866306, -95.394667 - Nearby events: https://openairdocs.org/map.md?lat=45.8663&lon=-95.3947&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-climb to cruise: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Central Region - Parties: FAA - NTSB case key (mKey): 102633 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN21LA128 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/102633/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=102633 - Page: https://openairdocs.org/ntsb/CEN21LA128 ## Probable cause The helicopter’s impact with an object on departure that could not be determined. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Object/animal/substance](https://openairdocs.org/ntsb-findings/03022000): Environmental issues › Physical environment · Effect on equipment; cases with it: [Agustawestland Philadelphia AW119MKII, 1 case](https://openairdocs.org/ntsb-findings/03022000/cases.md?model=0260401), [All aircraft, 224 cases](https://openairdocs.org/ntsb-findings/03022000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-climb to cruise: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) (defining event); cases with it: [Agustawestland Philadelphia AW119MKII, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=0260401), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The airline transport pilot of the commercial air medical flight reported that during a climbing left turn on departure, he heard a “thud.” He confirmed with the crew they had not dropped anything, and they affirmed they had not. The pilot believed the helicopter had hit something and elected to return to the departure airport. The pilot scanned the air to find what they could have impacted but did not see anything and then assumed a cowling had become unlatched due to the cold and vibration. He landed and left the helicopter running while the crew looked over the helicopter. At this time, the pilot was notified the trip was cancelled so he shut down, refueled, and moved the helicopter into the hangar. Once in the hangar, the pilot noticed the leading edge of the main rotor blade was a dented with a hole through the blade just aft of the dent. What caused the substantial damage to the main rotor blade was not determined. The pilot reported there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation. ## Aircraft - Registration: [N352LL](https://openairdocs.org/aircraft/N352LL), registered now, S/N 14820, built 2014 (OpenAirDocs) - Reported make and model: AGUSTAWESTLAND PHILADELPHIA CO AW119MKII - Registry model: [Agustawestland Philadelphia AW119MKII](https://openairdocs.org/model/agustawestland-philadelphia-aw119mkii) (registry code 0260401) (OpenAirDocs) - Registry engine: [Pratt & Whitney Canada PT6B-37A](https://openairdocs.org/engine/pratt-whitney-canada-pt6b-37a) (registry code 52179, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 14820 - Year built: 2014 - Airframe hours: 2631 - Engines: P&W CANADA PT6B-37A 900 horsepower turbo shaft - Damage: Substantial damage - Flight: Part 135 - Operator: Critical Care Services Inc DBA - Registered owner: Critical Care Services Inc DBA - Airworthiness certificate: Standard, Normal - Last inspection: Continuous airworthiness, February 12, 2021, 2,468 hours before - Destination: Gleenwood, MN - Flight plan: Company VFR - Airport: AXN, Chandler Fld ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 32; injuries: none; airline transport; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review June 19, 2020; seat: right; flight hours: 2,723 total, 590 in this make and model, 2,550 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: 360° at 3 knots - Visibility: 10 statute miles - Temperature: -9 °F, dew point -20 °F - Altimeter: 30.45 inHg - Observed at: KAXN - METAR: KAXN 131653Z AUTO 36003KT 10SM CLR M23/M29 A3045 RMK AO2 SLP364 T12331294 ## 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 20210213000199A](https://openairdocs.org/incident/20210213000199A), Feb 13, 2021: Agustawestland Philadelphia Co AW119MKII, Alexandria, MN, Substantial damage. 2021-02-13, N352LL, lifelinkiii augusta, helicopter took off from Alexandria, MN (kaxn) airport and hit an object with one rotor blade. After transitioning… ## Docket (2 files) The files NTSB released with the investigation on June 9, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=102633. 5.4 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 4.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12245776&FileExtension=pdf&FileName=Form%206120.1%20-N352LL-37CA176Q%20signed%20with%20blocks_Redacted-Rel.pdf - Photographs of damage (item 2, PDF, 3 pages, 869 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12249770&FileExtension=pdf&FileName=CEN21LA128%20Photos%20for%20Docket-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.