# NTSB GAA18CA429: Cessna 170, N432W, Spearfish, SD, July 19, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: July 19, 2018, 08:30 local (14:30 UTC) - Place: Spearfish, SD - Coordinates: 44.480834, -103.783332 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.4808&lon=-103.7833&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff-rejected takeoff: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report March 18, 2019 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 97824 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA18CA429 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97824/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97824 - Page: https://openairdocs.org/ntsb/GAA18CA429 ## Probable cause The pilot’s improper decision to take off in tailwind conditions, which resulted in an aborted takeoff with insufficient runway remaining. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Cessna 170B, 15 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=2072306), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Cessna 170B, 91 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=2072306), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Wind: tailwind](https://openairdocs.org/ntsb-findings/03034015): Environmental issues › Conditions/weather/phenomena · Decision related to condition (probable cause); cases with it: [Cessna 170B, 12 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md?model=2072306), [All aircraft, 594 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md) - [Wind: tailwind](https://openairdocs.org/ntsb-findings/03034015): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Cessna 170B, 12 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md?model=2072306), [All aircraft, 594 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md) - [Object/animal/substance: tree(s)](https://openairdocs.org/ntsb-findings/03022020): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Cessna 170B, 6 cases](https://openairdocs.org/ntsb-findings/03022020/cases.md?model=2072306), [All aircraft, 933 cases](https://openairdocs.org/ntsb-findings/03022020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff-rejected takeoff: Miscellaneous/other](https://openairdocs.org/ntsb-events/900); cases with it: [Cessna 170B, 2 cases](https://openairdocs.org/ntsb-events/900/sequence.md?model=2072306), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) - [Takeoff-rejected takeoff: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241); cases with it: [Cessna 170B, 9 cases](https://openairdocs.org/ntsb-events/241/sequence.md?model=2072306), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Takeoff-rejected takeoff: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Cessna 170B, 37 cases](https://openairdocs.org/ntsb-events/300/sequence.md?model=2072306), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md) - [Takeoff-rejected takeoff: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) (defining event); cases with it: [Cessna 170B, 6 cases](https://openairdocs.org/ntsb-events/490/sequence.md?model=2072306), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md) ## 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. ## Factual narrative The pilot reported that, during takeoff on a grass runway, after lift-off, he noticed he was not able to climb at a normal rate. He lowered the nose of the airplane, 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, 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, temperature 64°F, dew point 59°F. The airplane was departing on runway 26. The pilot did not submit the NTSB Form 6120.1 Pilot/Operator Aircraft Accident/Incident Report. ## Aircraft - Registration: [N432W](https://openairdocs.org/deregistered/N432W-2019-11-29), registration cancelled 2019-11-29, S/N 20325, built 1952 (OpenAirDocs) - Reported make and model: Cessna 170 (B) - Registry model: [Cessna 170B](https://openairdocs.org/model/cessna-170b) (registry code 2072306) (OpenAirDocs) - Registry engine: [Continental C145 series](https://openairdocs.org/engine/continental-c145-series) (registry code 17012, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 20325 - Year built: 1952 - Engines: Continental C145 SERIES 145 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Departed: SPF, Spearfish, SD - Destination: ECS, Newcastle, WY - Flight plan: Unknown - Airport: SPF, Black Hills-Clyde Ice Field, runway 26, 4,003 × 100 ft, grass/turf - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; injuries: none; private; airplane ratings: single-engine land; medical: class 2, without waivers/limitations ## Weather - Conditions: Visual (VMC), Day - Wind: 140° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 64 °F, dew point 59 °F - Altimeter: 30.02 inHg - Observed at: KSPF ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20180719011719A](https://openairdocs.org/incident/20180719011719A), Jul 19, 2018: Cessna 170B, Spearfish, SD, Substantial damage. On July 19, 2018 at approximately 08:30 MDT a Cessna 170B [privacy data omitted] went off the end of runway 26 and hitting a tree after takeoff during a CFR… ## Other investigations on N432W (2) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB CHI99LA106](https://openairdocs.org/ntsb/CHI99LA106), Mar 8, 1999: Cessna 170B (N432W), Grand Ledge, MI, substantial damage. Probable cause: the flight instructor's failure to successfully take remedial action to maintain directional control of the airplane during the landing roll out. Factors were the crosswinds and snowbank. - [NTSB CHI92LA087](https://openairdocs.org/ntsb/CHI92LA087), Feb 2, 1992: Cessna 170 (N432W), Howell, MI, substantial damage. Probable cause: DIRECTIONAL CONTROL WAS NOT MAINTAINED BY THE PILOT. A FACTOR RELATED TO THE ACCIDENT WAS: A CROSS WIND. ## Docket (2 files) The files NTSB released with the investigation on October 11, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97824. 972 KB in all. - Pilot's Statement (item 1, .PDF, 47 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40467347&FileExtension=.PDF&FileName=Pilot%27s%20Statement-Master.PDF - Accident Photo (item 2, .PDF, 1 photo, 925 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40467348&FileExtension=.PDF&FileName=Accident%20Photo-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.