CEN20LA068

NTSB accident investigation · Bell 407 · Minot, ND · January 22, 2020

Accident · No injuriesClass 3 · LimitedFinal report
Date
January 22, 2020, 13:32 local (19:32 UTC)
Place
Minot, ND
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N947LHBell 407
Defining event
Landing-flare/touchdown: Collision during takeoff/land
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Central Region
Parties
FAA FSDO
FAA report
20200122004599A
Case key
100876

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

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Probable cause

The pilot's failure to maintain clearance from fencing around the landing pad during landing, which resulted in the tail rotor contacting the fence.

Findings · 4

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.

Performance/control parameters: landing flareAircraft › Aircraft oper/perf/capability · Incorrect use/operationBell 407: 3 casesAll aircraft: 1,285 casesProbable cause
Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotBell 407: 19 casesAll aircraft: 9,295 casesProbable cause
Object/animal/substance: fence/fence postEnvironmental issues › Physical environment · Contributed to outcomeBell 407: 1 caseAll aircraft: 313 casesProbable cause
Object/animal/substance: fence/fence postEnvironmental issues › Physical environment · Response/compensationBell 407: 1 caseAll aircraft: 313 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 pilot departed on a positioning flight to pick up a medical crew. As he neared the helipad, he performed a right 180° circling approach. After completing the turn, the pilot thought he was a little low on final approach, and "pulled in a little collective" as he leveled the helicopter, which contacted the landing pad "firmly." Before the subsequent departure, the pilot felt a vibration, and he shut down the helicopter to investigate. The crew walked toward the tail and noticed a slight bend in the lower vertical fin, the tips of both tail rotor blades missing, and the helipad safety fence missing a small section of the fence-edge pipe. Further examination of the helicopter identified cracks in the tail boom structure. A security camera video of the helipad showed that the helicopter's tail rotor impacted the fence during the landing.

Factual narrative

On January 22, 2019, about 1332 central standard time, a Bell 407 helicopter, N947LH, impacted a helipad perimeter fence during a landing near Minot, North Dakota. The pilot, sole occupant was not injured, and the helicopter sustained substantial damage. The helicopter was registered to and operated by Executive Air Taxi Corp under the provisions of Title 14 Code of Federal Regulations Part 91 as a positioning flight. Day visual meteorological conditions prevailed for the flight. The pilot conducted a flight to the Trinity Medical Helipad (2ND4) to pick up the medical crew. The pilot stated he performed a right 180° circling approach to the helipad. As he finished the turn, he thought he was a little low on final approach and "pulled in a little collective." He applied more collective as he was leveling off and the "helicopter contacted the pad firmly." The pilot added that it was firmer than a normal landing, but he thought everything was okay until he noticed a small vibration. Before departing with the medical crew, the pilot still felt the vibration in the helicopter, so he shut the helicopter down to check. After shutdown, the crew walked toward the tail and noticed a slight bend in the lower vertical fin, the tips of both tail rotor blades missing, and the helipad safety fence was missing a small section of the fence-edge pipe. Additional examination of the helicopter identified cracks in the tailboom structure. A review of security camera video of the helipad showed the helicopter's tail rotor impact with the edge-fencing.

Aircraft

Registration
N947LH
Reported as
Bell 407 (No Series)
Category
Helicopter
Serial number
53509
Built
2001
Airframe hours
7,601.9
Engine
Allison 250-C47, 650 horsepower, turbo shaft
Damage
Substantial damage
Flight
Positioning · Part 91
Operator
Executive Air Taxi Corp
Registered owner
Executive Air Taxi Corp
Airworthiness certificate
Standard, Normal
Last inspection
Continuous airworthiness · December 26, 2019
Departed
KMOT · Minot, ND
Destination
2ND4 · Minot, ND
Flight plan
Company VFR
Airport
2ND4 · Trinity Health

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
60
Injuries
None
Certificate
Airline transport
Instrument ratings
Helicopter
Medical
Class 2, Without waivers/limitations
Last flight review
July 18, 2019
Seat
Right
Restraint
3-point
Flight hours
6,340.7 total · 98 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
300° at 6 knots
Visibility
10 statute miles
Temperature
28 °F, dew point 21 °F
Altimeter
29.78 inHg
Observed at
KMOT, 2 nm away

Docket · 3

The files NTSB released with the investigation on March 18, 2020, 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.