# NTSB CEN18CA072: Bell Helicopter Textron Canada 407, N214AM, Norfolk, NE, January 5, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: January 4, 2018, 19:00 local (Jan 5, 2018, 01:00 UTC) - Place: Norfolk, NE - Coordinates: 42.022499, -97.413612 - Nearby events: https://openairdocs.org/map.md?lat=42.0225&lon=-97.4136&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed, report February 21, 2018 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA FSDO - NTSB case key (mKey): 96587 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN18CA072 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/96587/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=96587 - Page: https://openairdocs.org/ntsb/CEN18CA072 ## Probable cause Maintenance personnel’s failure to properly secure the tail rotor drive shaft cover, which resulted in the cover departing the helicopter in flight. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Maintenance: scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Bell Helicopter Textron Canada 407, 1 case](https://openairdocs.org/ntsb-findings/02062010/cases.md?model=1182154), [All aircraft, 320 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md) - [Maintenance/inspections](https://openairdocs.org/ntsb-findings/01010500): Aircraft › Aircraft handling/service · Incorrect service/maintenance (probable cause); cases with it: [Bell Helicopter Textron Canada 407, 1 case](https://openairdocs.org/ntsb-findings/01010500/cases.md?model=1182154), [All aircraft, 103 cases](https://openairdocs.org/ntsb-findings/01010500/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Prior to flight: Aircraft maintenance event](https://openairdocs.org/ntsb-events/040); cases with it: [Bell Helicopter Textron Canada 407, 2 cases](https://openairdocs.org/ntsb-events/040/sequence.md?model=1182154), [All aircraft, 484 cases](https://openairdocs.org/ntsb-events/040/sequence.md) - [Enroute: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338) (defining event); cases with it: [Bell Helicopter Textron Canada 407, 1 case](https://openairdocs.org/ntsb-events/338/sequence.md?model=1182154), [All aircraft, 563 cases](https://openairdocs.org/ntsb-events/338/sequence.md) ## Analysis The pilot and two medical crewmembers were on a return flight to a hospital helipad. During the approach to the helipad, the crew heard a noise outside the helicopter. The medical crewmembers reported they felt a slight "shudder" on the helicopter but attributed it to the wind as they approached the helipad. The pilot heard the noise, but there was no effect on the controls or flight characteristics, so he continued the landing without further incident. After engine shutdown, the oncoming pilot noticed that the helicopter's tail rotor drive shaft cover was missing. The surrounding area near the helicopter's approach path was searched, and the missing cover was found. An examination of the helicopter noted substantial damage to the tail rotor drive shaft. The day before the accident, scheduled maintenance was performed on the helicopter's tail rotor pitch change mechanism, which required removal of the drive shaft cover. The cover was reinstalled, and no problems were reported during a subsequent preflight inspection. It is likely that maintenance personnel did not properly secure the cover fasteners after the cover was reinstalled. ## Factual narrative The pilot and two medical crewmembers were on a return flight to a hospital helipad. During the approach to the helipad, the crew heard a noise outside the helicopter. The medical crewmembers reported they felt a slight "shudder" on the helicopter but attributed it to the wind as they approached the helipad. The pilot heard the noise, but there was no effect on the controls or flight characteristics, so he continued the landing without further incident. After engine shutdown, the on-coming pilot noticed the helicopter's tail rotor drive shaft cover missing. A search of the surrounding area near the helicopter's approach path, located the missing cover. An examination of the helicopter noted substantial damage to the tail rotor drive shaft. The day prior to the accident, scheduled maintenance was performed on the helicopter's tail rotor pitch change mechanism, which required removal of the drive shaft cover. The cover was reinstalled, and no problems were reported during a subsequent pre-flight inspection. It is likely the cover fasteners were not properly secured, after the cover was re-installed. ## Aircraft - Registration: [N214AM](https://openairdocs.org/aircraft/N214AM), registered now, S/N 54485, built 2014 (OpenAirDocs) - Reported make and model: BELL HELICOPTER TEXTRON CANADA 407 (NO SERIES) - Registry model: [Bell Helicopter Textron Canada 407](https://openairdocs.org/model/bell-helicopter-textron-canada-407) (registry code 1182154) (OpenAirDocs) - Registry engine: [Rolls-Royce 250-C47B](https://openairdocs.org/engine/rolls-royce-250-c47b) (registry code 54585, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 54485 - Year built: 2014 - Engines: ROLLS-ROYC 250-C47B turbo shaft - Damage: Substantial damage - Flight: Positioning, Part 135 - Operator: Air Methods Corp - Registered owner: Air Methods Corp - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, January 3, 2018 - Departed: Omaha, NE - Destination: Norfolk, NE - Flight plan: Company VFR - Equipment: Satellite tracking device ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 63; injuries: none; airline transport; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 2, with waivers/limitations; seat: right; restraint: 4-point ## Weather - Conditions: Visual (VMC), Night/dark - Wind: 90° at 5 knots - Temperature: 9 °F, dew point 7 °F ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Incident 20180104006179I](https://openairdocs.org/incident/20180104006179I), Jan 4, 2018: Bell Helicopter Textron Canada 407, Norfolk, NE, Minor damage. The pilot and two medical crewmembers were on a return flight to a hospital helipad. During the approach to the helipad, the crew heard a noise outside the… ## Docket (2 files) The files NTSB released with the investigation on January 25, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=96587. 977 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 847 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40459516&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Crew Statements (item 2, .PDF, 131 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40459517&FileExtension=.PDF&FileName=Crew%20Statements-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.