# NTSB GAA18CA370: Cessna 170, N4427B, Anchorage, AK, June 21, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: June 21, 2018, 10:20 local (18:20 UTC) - Place: Anchorage, AK - Coordinates: 61.17889, -149.964447 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=61.1789&lon=-149.9644&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report March 18, 2019 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 97549 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA18CA370 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97549/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97549 - Page: https://openairdocs.org/ntsb/GAA18CA370 ## Probable cause The pilot’s failure to maintain directional control during landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Cessna 170B, 74 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=2072306), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/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) - [Object/animal/substance](https://openairdocs.org/ntsb-findings/03022000): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Cessna 170B, 2 cases](https://openairdocs.org/ntsb-findings/03022000/cases.md?model=2072306), [All aircraft, 224 cases](https://openairdocs.org/ntsb-findings/03022000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Cessna 170B, 84 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=2072306), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Landing: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Cessna 170B, 13 cases](https://openairdocs.org/ntsb-events/060/sequence.md?model=2072306), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md) ## Analysis The pilot of the float-equipped airplane reported that, during landing, the touchdown on the water was smooth. While the airplane was on step, she reduced the flaps, and the airplane suddenly veered left. She applied right rudder and reduced engine power. The left float hit the concrete shore bank, the airplane spun to the left, and the right wing struck the shore. The airplane sustained substantial damage to the fuselage and both wings. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. ## Factual narrative The pilot of the float-equipped airplane reported that, during landing, the touchdown on the water was smooth. While the airplane was on step, she reduced the flaps and the airplane suddenly veered left. She applied right rudder and reduced engine power. The left float hit the concrete shore bank, the airplane spun to the left, and the right wing struck the shore. The airplane sustained substantial damage to the fuselage and both wings. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. ## Aircraft - Registration: [N4427B](https://openairdocs.org/aircraft/N4427B), registered now, S/N 26771, built 1955 (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: 26771 - Year built: 1955 - Airframe hours: 4352.9 - Engines: Lycoming O-360-A1A 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 28, 2018 - Departed: Skwentna, AK - Destination: LHD, Anchorage, AK - Airport: LHD, Lake Hood, runway W, 4,541 × 188 ft, water - Equipment: Handheld GPS, Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 57; injuries: none; private; airplane ratings: single-engine land, single-engine sea; medical: class 3, with waivers/limitations; last flight review October 6, 2017; seat: left; restraint: none; flight hours: 760 total, 670 in this make and model, 642 as pilot in command, 6 in the last 90 days, 6 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Temperature: 61 °F, dew point 52 °F - Altimeter: 29.73 inHg - Observed at: PALH ## 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 20180621008349A](https://openairdocs.org/incident/20180621008349A), Jun 21, 2018: Cessna 170B, Anchorage, AK, Substantial damage. Pilot touched down on the lake and attempted to retract flaps while taxiing at high-speed (on step). Aircraft veered to the left and contacted the bank at an… ## Other investigations on N4427B (1) 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 GAA19CA364](https://openairdocs.org/ntsb/GAA19CA364), Jun 17, 2019: Cessna 170 (N4427B), Hewitt Lake, AK, substantial damage. Probable cause: The pilot's failure to maintain directional control during takeoff from a soft, grass airstrip, which resulted in impact with brush. ## Docket (2 files) The files NTSB released with the investigation on October 2, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97549. 1.2 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 864 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40467087&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Accident Picture (item 2, .PDF, 1 photo, 343 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40467088&FileExtension=.PDF&FileName=Accident%20Picture-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.