- Date
- August 5, 2020, 17:45 local (22:45 UTC)
- Place
- Delia, KS
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N104SUHughes 369
- Defining event
- Maneuvering-low-alt flying: Miscellaneous/other
- Weather
- Visual (VMC) · Day
- Status
- Completed
- Report
- Approved by Office Director
- Investigation class
- Class 4 - Basic report with no Prelim publish
- NTSB office
- Central Region
- FAA report
- 20200805009889A
- Case key
- 101782
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
Foreign object damage sustained to the main rotor blades due to aerial tree trimming.
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.
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
While conducting an aerial tree-trimming flight with an external load aerial saw, the pilot heard a loud “thump” and felt a collision. A heavy vibration was felt, and the pilot landed in a nearby cornfield without further incident. Upon landing substantial damage was found to the main rotor blades with embedded pieces of tree bark and vegetation found in the blades. The pilot reported that there were no mechanical malfunctions that contributed to the accident. The aerial saw was suspended about 120 ft below the helicopter. The operator noted that this distance is normally adequate to prevent foreign object damage (FOD) to the main rotor blades.
Aircraft
- Registration
- N104SU
- Reported as
- Hughes 369 (D)
- Category
- Helicopter
- Serial number
- 670151D
- Built
- 1977
- Airframe hours
- 9,856.3
- Engine
- Rolls-Royce 250-C20B, 420 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- External load · Part 133
- Operator
- Signature Utility, doing business as Signature Utility Services LLC
- Registered owner
- Signature Utility
- Airworthiness certificate
- Standard, Normal
- Last inspection
- 100 hour · July 9, 2020 · 34.9 hours before
- Departed
- Delia, KS
- Destination
- Delia, KS
- Equipment
- Electronic flight bag or handheld device, ADS-B, Satellite tracking device, Handheld GPS, Onboard weather
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
- 39
- Injuries
- None
- Certificates
- Private, Commercial
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Without waivers/limitations
- Last flight review
- January 10, 2019
- Seat
- Left
- Restraint
- 3-point
- Flight hours
- 5,260 total · 3,230 in this make and model · 5,160 as pilot in command · 75 in the last 90 days · 30 in the last 30 days · 5 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 120° at 8 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 79 °F, dew point 59 °F
- Altimeter
- 29.98 inHg
- Observed at
- KTOP, 20 nm away
Docket · 2
The files NTSB released with the investigation on July 29, 2021, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.0 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.