ERA16LA265

NTSB accident investigation · Eurocopter Deutschland MBB BK 117 C-2 · Pittsburgh, PA · April 26, 2016

Accident · No injuriesLimited investigationFinal report
Date
April 26, 2016, 15:00 local (19:00 UTC)
Place
Pittsburgh, PA
Injuries
5 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N145HNEurocopter Deutschland MBB BK 117 C-2
Defining event
Enroute-cruise: Miscellaneous/other
Weather
Visual (VMC) · Day
Status
Completed · report May 25, 2017
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20160426006189I
Case key
93663

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

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.

Findings · 2

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

MaintenancePersonnel issues › Task performance · Maintenance personnelAll aircraft: 143 casesProbable cause
FuselageAircraft › Aircraft structures · Incorrect service/maintenanceAll aircraft: 4 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

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.

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.

Aircraft

Registration
N145HN
Reported as
Eurocopter Deutschland MBB BK 117 C-2 (C2)
Category
Helicopter
Serial number
9302
Built
2009
Airframe hours
3,362
Engines
Turbomeca Arriel 1E2, 665 horsepower, turbo shaftTurbomeca Arriel 1E2, 665 horsepower, turbo shaft
Damage
Substantial damage
Flight
Part 135
Operator
Air Methods Corp
Registered owner
Healthnet Aeromedican Services Inc
Airworthiness certificate
Standard, Transport
Last inspection
AAIP · April 22, 2016 · 16 hours before
Departed
22WV · Grafton, WV
Destination
PN80 · Pittsburgh, PA
Flight plan
Company VFR
Airport
PN80 · West Penn Hospital Heliport
Equipment
Satellite tracking device, Onboard weather, Electronic multifunction display, Auto-pilot

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
45
Injuries
None
Certificate
Commercial
Instrument ratings
Helicopter
Medical
Class 2, Without waivers/limitations
Last flight review
October 8, 2015
Seat
Right
Restraint
4-point
Flight hours
5,246 total · 478 in this make and model · 5,246 as pilot in command · 68 in the last 90 days · 28 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
250° at 16 knots
Visibility
10 statute miles
Lowest ceiling
5,000 ft broken
Temperature
73 °F, dew point 55 °F
Altimeter
29.73 inHg
Observed at
AGC, 8 nm away

Docket · 3

The files NTSB released with the investigation on April 3, 2017, on NTSB’s docket system: statements, records, photos and specialists’ reports. 2.5 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.