- Date
- August 15, 2008, 07:00 local (12:00 UTC)
- Place
- Cokato, MN
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N945HAHiller UH-12E
- Defining event
- Maneuvering-low-alt flying: Low altitude operation/event
- Weather
- Visual (VMC) · Day
- Status
- Completed · report September 26, 2008
- Report
- Approved by Office Director
- Parties
- Minneapolis, MN FSDO
- FAA report
- 20080815850449A
- Case key
- 68873
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
The pilot did not visually identify and maintain clearance with the power lines, and the pilot's inability to maintain control of the helicopter once it contacted the power lines. Factors associated with the accident were the low altitude operations being conducted and the power lines.
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.
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 reported he made three passes over the fields that he was going to spray. He stated he noticed a power line pole that had a transformer cover on it and what appeared to be a wire covering running up the pole. This led the pilot to believe that the power lines in the area were buried. The pilot then landed and loaded the chemicals. He stated that after taking off with the load, he flew one more pass to look for power lines and still did not see any. He stated that during the first swath run, the helicopter contacted power lines. The helicopter initially pitched nose up and to the right. The pilot stated he pushed the nose down and to the left, but the power lines wrapped around the control tubes and tail rotor. The helicopter then entered a descending spin. The pilot stated he pulled back to flatten the descent just prior to the helicopter contacting the ground.
Factual narrative
On August 15, 2008, at 0700 central daylight time, a Hiller UH-12E helicopter collided with the terrain after contacting unmarked power lines during an aerial application flight in Cokato, Minnesota. The pilot was not injured and the helicopter was substantially damaged. The flight was operating under Title 14 Code of Federal Regulations Part 137. Visual meteorological conditions prevailed and no flight plan was filed. The local flight originated just prior to the accident. The pilot reported he made three passes over the fields that he was going to spray. He stated he noticed a power line pole that had a transformer cover on it and what appeared to be a wire covering running up the pole. This led the pilot to believe that the power lines in the area were buried. The pilot then landed and loaded the chemicals. He stated that after taking off with the load, he flew one more pass to look for power lines and still did not see any. He stated that during the first swath run, the helicopter contacted power lines. The helicopter initially pitched nose up and to the right. The pilot stated he pushed the nose down and to the left, but the power lines wrapped around the control tubes and tail rotor. The helicopter then entered a descending spin. The pilot stated he pulled back to flatten the descent just prior to the helicopter contacting the ground.
Aircraft
- Registration
- N945HA
- Reported as
- Hiller UH-12E
- Category
- Helicopter
- Serial number
- 2057
- Engine
- Lycoming VO-540, reciprocating
- Damage
- Substantial damage
- Flight
- Aerial application · Part 137
- Registered owner
- Triple H Aviation Inc
- Airworthiness certificate
- Special, Restricted (Special)
- Departed
- Cokato, MN
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
- 36
- Certificate
- Commercial
- Medical
- Class 2, With waivers/limitations
- Flight hours
- 804 total · 703 in this make and model · 620 as pilot in command
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 30° at 2 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 64 °F
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.