ERA16LA265
2016-04-26 · Pittsburgh, Pennsylvania, United States · None · 1 aircraft · Status: Completed
Airport PN80
Aircraft involved
Probable cause & findings
Maintenance personnel’s failure to properly secure the left vertical fin cowling during recent maintenance, which resulted in its separation and subsequent contact with the tail rotor system during flight.
Factual narrative
On April 26, 2016, about 1500 eastern daylight time, a Eurocopter Deutchland GMBH MBB-BK-117 C-2, N145HN, operated by Air Methods Corp, was substantially damaged during cruise flight to West Penn Hospital Heliport (PN80), Pittsburgh, Pennsylvania. The commercial pilot, three crewmembers and one patient were not injured. The on-demand air medical flight was conducted under the provisions of 14 Code of Federal Regulations Part 135. Visual meteorological conditions prevailed and a company flight plan was filed for the flight that originated from Grafton City Hospital Heliport (22WV), Grafton, West Virginia, about 1430.The pilot reported that the patient transfer flight was the second flight of the day, following maintenance work that was performed on the helicopter earlier that morning. The patient transfer flight was uneventful; however, after landing the pilot noticed that the left vertical fin cowling had partially separated and came in contact with a tailrotor blade. The pilot added that 8 of the 11 fasteners on the left vertical fin cowling were unlocked. Examination of the tailrotor blade by representatives from the helicopter manufacturer revealed that the tailrotor blade had sustained substantial damage. Examination of the helicopter by a Federal Aviation Administration inspector revealed that the Dzus fasteners on the right vertical fin cowling remained secured while the Dzus fasteners on the left vertical fin cowling were unlocked, consistent with them not being properly secured by maintenance personnel following the maintenance work that was performed. Additionally, the operator reported that there were no mechanical failures or malfunctions with the helicopter. The accident flight, which was an on-demand air medical flight, was the second flight of the day following maintenance work that had been performed on the helicopter earlier that morning. The commercial pilot reported that the flight was uneventful but that, after landing, he noticed that the left vertical fin cowling had partially separated and contacted a tail rotor blade. Further examination of the helicopter revealed that the right vertical fin cowling remained secured but that 8 of the 11 fasteners on the left vertical fin cowling were unlocked, consistent with maintenance personnel not properly securing them following the maintenance work that was performed earlier that day. Source: NTSB Aviation Accident Database Retrieved: 2026-02-12
NTSB Findings
FAA avdata. C = Cause, F = Factor.
- C Personnel issues-Task performance-Maintenance-(general)-Maintenance personnel - C
- C Aircraft-Aircraft structures-Fuselage-(general)-Incorrect service/maintenance - C
Verbatim from NTSB's published report. Source file
NTSB_2016_ERA16LA265.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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Related research
Matched on aircraft type or causal vocabulary (maintenance). All research papers
- Embry-Riddle Scholarly Commons 2026 · Journal article (IJAAA) From Reactive to Predictive: A hybrid Trust-Mediated Adoption Framework for Data-Driven Maintenance in Distributed-Authority Aviation Environments
Modern aviation maintenance operates within increasingly data-intensive technological environments, yet the operational integration of predictive maintenance into routine decision-making remains incon…
- Semantic Scholar 2026 · Article (Reliability Engineering & System Safety) Understanding human error in military aviation maintenance: The role of Performance shaping factors, cognitive workload and error orientation
- Semantic Scholar 2025 · Article (Applied Sciences) Decision-Making Framework for Aviation Safety in Predictive Maintenance Strategies
The implementation of predictive maintenance (PM) in aviation presents unique challenges due to strict safety requirements, complex operational environments, and regulatory constraints.
- Semantic Scholar 2024 · Article (Defence Science Journal) Modelling of Human Factors in Aviation Maintenance Using HFACS ME Human Factors Analysis and Classification System Maintenance Extension and Bayesian Network
Aircraft maintenance is a complex task involving a skilled human workforce, spare parts, and various other resources. Human factors are an inherent element of the human workforce.
- Embry-Riddle Scholarly Commons 2024 · Journal article (JAAER) A New Trajectory in UAV Safety: Leveraging Reinforcement Learning for Distance Maintenance Under Wind Variations
In the field of aviation, safety is a critical cornerstone, and the operation of Unmanned Aerial Vehicle (UAV) systems is deeply connected with this principle.
- Embry-Riddle Scholarly Commons 2024 · Journal article (JAAER) Low-Resource Automatic Speech Recognition Domain Adaptation – A Case-Study in Aviation Maintenance
With timeliness and efficiency being critical in the aviation maintenance industry, the need has been growing for smart technological solutions that optimize and streamline the different underlying ta…