- Date
- September 4, 2015, 07:55 local (13:55 UTC)
- Place
- Fort Pierre, SD
- Injuries
- 1 minor
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N321DAAir Tractor AT 402A
- Defining event
- Maneuvering: Controlled flight into terr/obj (CFIT)
- Weather
- Visual (VMC) · Day
- Status
- Completed · report October 8, 2015
- Report
- Approved by Office Director
- NTSB office
- General Aviation Accidents
- Parties
- FAA Rapid City FSDO
- FAA report
- 20150904012839A
- Case key
- 91942
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's failure to maintain obstacle clearance, which resulted in the airplane striking guy-wires during aerial application operations.
Findings · 3
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 that after conducting a pass over a field during an aerial application flight, he passed clear of a tower but did not see the tower support guy-wires and collided with them. He stated, "After the guy-wire impact there was an immediate sound of the engine starting to lose power and/or shut down." The pilot then performed an emergency landing on a gravel road without further incident. A post flight inspection revealed substantial damage to the fuselage and left wing. The pilot reported there were no pre-impact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.
Factual narrative
The pilot reported that after conducting a pass over a field during an aerial application flight, he passed clear of a tower but did not see the tower support guy-wires and collided with them. He stated, "After the guy-wire impact there was an immediate sound of the engine starting to lose power and/or shut down." The pilot then performed an emergency landing on a gravel road without further incident. A post flight inspection revealed substantial damage to the fuselage and left wing. The pilot reported there were no pre-impact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. ADDITIONAL INFORMATION Aviation Life Support Systems The pilot reported that he was wearing a Gentex Corporation HGU-55/E helmet for the flight. He stated, "The face shield/visor protected my eyes and upper face from impact injuries of the windshield/miscellaneous debris and also from engine oil." He also stated that, "The helmet itself protected my head from physical injury." The helmet sustained no noticeable damage from the accident. The Air Tractor AT-402 airplane flight manual states the following placard must be displayed, "Occupant must attach seatbelt and shoulder harness and wear a DOT approved or mil-spec crash helmet."
Aircraft
- Registration
- N321DA
- Reported as
- Air Tractor AT 402A (A)
- Category
- Airplane
- Serial number
- 402A-0814
- Built
- 1991
- Airframe hours
- 9,401.6
- Engine
- Pratt & Whitney PT6A-15AG, 680 horsepower, turbo prop
- Damage
- Substantial damage
- Flight
- Aerial application · Part 137
- Operator
- Randy A. Yost / Barbara J. Yost
- Registered owner
- Randy A. Yost / Barbara J. Yost
- Airworthiness certificate
- Special, Restricted (Special)
- Last inspection
- Annual · January 10, 2015
- Departed
- SD21 · Hayes, SD
- Destination
- SD21 · Hayes, SD
- Equipment
- Stall warning system
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
- 23
- Injuries
- Minor
- Certificate
- Commercial
- Airplane ratings
- Single-engine land
- Instrument ratings
- Airplane
- Medical
- Class 2, Waiver time limited special
- Last flight review
- March 10, 2014
- Seat
- Single
- Restraint
- 5-point
- Flight hours
- 1,875 total · 77 in this make and model · 1,833 as pilot in command · 319 in the last 90 days · 113 in the last 30 days
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 20° at 8 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 70 °F, dew point 64 °F
- Altimeter
- 29.69 inHg
- Observed at
- KPIR, 13 nm away
Docket · 3
The files NTSB released with the investigation on September 29, 2015, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.3 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.