Cessna 170B, N432W: Accident occurred July 19, 2018 at Black Hills Airport-Clyde Ice Field (KSPF), Spearfish, Lawrence County, South Dakota

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Rapid City, South Dakota

Aviation Accident Final Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

Aviation Accident Data Summary - National Transportation Safety Board: https://app.ntsb.gov/pdf

http://registry.faa.gov/N432W

Location: Spearfish, SD
Accident Number: GAA18CA429
Date & Time: 07/19/2018, 0830 MDT
Registration: N432W
Aircraft: Cessna 170
Aircraft Damage: Substantial
Defining Event:
Injuries: 2 None
Flight Conducted Under: Part 91: General Aviation - Personal

Analysis 

The pilot reported that, during takeoff on a grass runway, after liftoff, he noticed the airplane was not able to climb at a normal rate. He lowered the airplane's nose, but the airspeed remained "dangerously low," and the stall horn sounded intermittently. He reduced power to abort the takeoff, but there was insufficient runway remaining. The airplane touched down and overran the runway, the left wing impacted a tree, and the airplane spun 180° before coming to rest.

The airplane sustained substantial damage to the left wing.

The automated weather observation station located on the airport reported that, about 5 minutes after the accident, the wind was from 140° at 5 knots. The airplane was departing from runway 26. 

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot's improper decision to take off in tailwind conditions, which resulted in an aborted takeoff with insufficient runway remaining.

Findings

Personnel issues
Decision making/judgment - Pilot (Cause)
Aircraft control - Pilot (Cause)

Environmental issues
Tailwind - Decision related to condition (Cause)
Tailwind - Effect on operation
Tree(s) - Contributed to outcome

Factual Information

History of Flight

Takeoff-rejected takeoff
Miscellaneous/other
Aerodynamic stall/spin
Runway excursion
Collision with terr/obj (non-CFIT) 

Pilot Information

Certificate: Private
Age: 31, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Unknown
Other Aircraft Rating(s): None
Restraint Used: Unknown
Instrument Rating(s): None
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 2 Without Waivers/Limitations
Last FAA Medical Exam: 09/02/2015
Occupational Pilot: No
Last Flight Review or Equivalent: 
Flight Time:

Aircraft and Owner/Operator Information

Aircraft Make: Cessna
Registration: N432W
Model/Series: 170 B
Aircraft Category: Airplane
Year of Manufacture: 1952
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 20325
Landing Gear Type: Tailwheel
Seats: 4
Date/Type of Last Inspection:  Unknown
Certified Max Gross Wt.: 2200 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time:
Engine Manufacturer: Continental
ELT:
Engine Model/Series: C145 SERIES
Registered Owner: On file
Rated Power: 145 hp
Operator: On file
Operating Certificate(s) Held: None 

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KSPF, 3931 ft msl
Distance from Accident Site: 0 Nautical Miles
Observation Time: 1335 UTC
Direction from Accident Site: 6°
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 5 knots /
Turbulence Type Forecast/Actual: None / None
Wind Direction: 140°
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 30.02 inches Hg
Temperature/Dew Point: 18°C / 15°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Spearfish, SD (SPF)
Type of Flight Plan Filed: Unknown
Destination: Newcastle, WY (ECS)
Type of Clearance: Unknown
Departure Time: 0830 MDT
Type of Airspace: Class G

Airport Information

Airport: BLACK HILLS-CLYDE ICE FIELD (SPF)
Runway Surface Type: Grass/turf
Airport Elevation: 3933 ft
Runway Surface Condition: Dry
Runway Used: 26
IFR Approach: None
Runway Length/Width: 4003 ft / 100 ft
VFR Approach/Landing: None

Wreckage and Impact Information

Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: 1 None
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 2 None
Latitude, Longitude:  44.480833, -103.783333 (est)