# NTSB WPR21LA017: Piper PA28, N4673R, Puyallup, WA, October 18, 2020 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: October 17, 2020, 17:42 local (Oct 18, 2020, 00:42 UTC) - Place: Puyallup, WA · Parking lot of Holy Disciples Catholic Church, Puyallup, WA - Coordinates: 47.0877, -122.29114 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.0877&lon=-122.2911&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern crosswind: Fuel related](https://openairdocs.org/ntsb-events/190) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 102172 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR21LA017 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/102172/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=102172 - Page: https://openairdocs.org/ntsb/WPR21LA017 ## Probable cause A partial loss of engine power as a result of carburetor icing and the flight instructors failure to use carburetor heat. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Temp/humidity/pressure: conducive to carburetor icing](https://openairdocs.org/ntsb-findings/03031030): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Piper PA-28-140, 10 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md?model=7102802), [All aircraft, 435 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md) - [Use of equip/info: use of equip/system](https://openairdocs.org/ntsb-findings/02063015): Personnel issues › Task performance · Instructor/check pilot (probable cause); cases with it: [Piper PA-28-140, 16 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md?model=7102802), [All aircraft, 1,391 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md) - [Ice/rain protection system: intake anti-ice, deice](https://openairdocs.org/ntsb-findings/01023020): Aircraft › Aircraft systems · Not used/operated (probable cause); cases with it: [Piper PA-28-140, 3 cases](https://openairdocs.org/ntsb-findings/01023020/cases.md?model=7102802), [All aircraft, 108 cases](https://openairdocs.org/ntsb-findings/01023020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern crosswind: Fuel related](https://openairdocs.org/ntsb-events/190) (defining event); cases with it: [Piper PA-28-140, 8 cases](https://openairdocs.org/ntsb-events/190/sequence.md?model=7102802), [All aircraft, 361 cases](https://openairdocs.org/ntsb-events/190/sequence.md) - [Approach-VFR pattern crosswind: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342); cases with it: [Piper PA-28-140, 47 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=7102802), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Approach-VFR pattern crosswind: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Piper PA-28-140, 56 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=7102802), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Piper PA-28-140, 137 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7102802), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The student pilot reported that they conducted two uneventful touch-and-go landings. After the second touch-and-go, they were climbing with full power through about 500 ft when the engine sputtered momentarily. The instructor took over the flight controls and continued a left crosswind when the engine power reduced to idle. The instructor turned the airplane back toward the airport and ensured the fuel selector was on, throttle and mixture were full forward, and magnetos on both. The student pilot pressed the starter to see if that would help, but the engine continued at idle, and the airplane continued to descend. Unable to make it to the airport, the instructor made an off-airport landing during which the airplane touched down momentarily and bounced back into ground effect. It impacted a few trees before coming to a stop in a parking lot. The airplane sustained substantial damage to the right wing and fuselage. A postaccident examination and run of the engine did not reveal any anomalies that would have precluded normal operation. The temperature and dewpoint conditions were plotted and fell on the line between serious icing at cruise power and serious icing at glide power. The instructor reported that he did not use carburetor heat once the engine started to sputter. ## Factual narrative On October 17, 2020, about 1742 Pacific daylight time, a Piper PA-28-140 airplane, N4673R, was substantially damaged when it was involved in an accident near Pierce County Airport – Thun Field (PLU), Puyallup, Washington. The flight instructor, one student, and one passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. The student pilot reported that they conducted an uneventful preflight, runup, and takeoff. They proceeded to PLU to conduct a few touch-and-go landings. The first was an uneventful soft field landing and takeoff. Since the traffic pattern was busy, they flew a wide pattern and had a slightly faster than normal approach to land. After the second touch-and-go they were climbing with full power through about 500 ft when the engine sputtered momentarily. The instructor took over the flight controls and continued on a left crosswind when the engine power reduced to idle. The instructor turned the airplane back toward the airport and ensured the fuel selector was on, throttle and mixture were full forward, and both magnetos on. The student pilot pressed the starter to see if that would help, but the engine continued to idle and the airplane continued to descend. Unable to reach the airport, the instructor performed an off-airport landing. The airplane touched down momentarily and bounced back into ground effect. It impacted a few trees before coming to a stop in a parking lot. The airplane sustained substantial damage to the right wing and fuselage. A postaccident examination of the engine did not reveal any anomalies that would have precluded normal operation. The engine was rotated by hand; continuity was established throughout the drivetrain, and thumb compression was established. The carburetor bowl was removed, and fuel was located within the bowl. When the throttle was moved, fuel expelled from the accelerator pump. A small fuel tank was connected to the right-wing fuel line and the engine was prepared for an engine run. The engine started normally and exhibited a little roughness but smoothed out within a few seconds. The fuel and oil pressure gauges indicated normal pressure. The throttle was manipulated, and the engine responded accordingly with no anomalies noted. The temperature and dewpoint were plotted on the FAA Carburetor Icing Chart. Conditions fell on the line between serious icing at cruise power and serious icing at glide power. The flight instructor reported to the FAA inspector that he did not use carburetor heat once the engine started to sputter. ## Aircraft - Registration: [N4673R](https://openairdocs.org/aircraft/N4673R), registered now, S/N 28-21430, built 1966 (OpenAirDocs) - Reported make and model: PIPER PA28 (140) - Registry model: [Piper PA-28-140](https://openairdocs.org/model/piper-pa-28-140) (registry code 7102802) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 28-21430 - Year built: 1966 - Airframe hours: 5616 - Engines: Lycoming O-320 150 hp reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 14, 2020 - Departed: 3B8, Spanaway, WA - Destination: Same as departure - Airport: PLU, Pierce County/Thun Field, runway 17, 3,651 × 60 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Student pilot; age 44; injuries: none; student; medical: class 3, without waivers/limitations; seat: left; restraint: lap only; flight hours: 10 total, 10 in this make and model, 10 in the last 90 days, 10 in the last 30 days, 1 in the last 24 hours - Flight instructor; age 22; injuries: none; flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review March 21, 2020; seat: right; restraint: lap only; flight hours: 437 total, 10 in this make and model, 340 as pilot in command, 135 in the last 90 days, 35 in the last 30 days ## Weather - Conditions: Visual (VMC), Dusk - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: 7,500 ft overcast - Temperature: 59 °F, dew point 46 °F - Altimeter: 30.18 inHg - Observed at: PLU, 1 nm away ## 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 20201017020089A](https://openairdocs.org/incident/20201017020089A), Oct 17, 2020: Piper PA-28-140, Puyallup, WA, Substantial damage. On October 18, 2020 at 0040 UTC, N4673R a PA-28-140 aircraft departed shady acres airport (3B8) to pierce co. Thun Field Airport (plu) on an instructional… ## Docket (8 files) The files NTSB released with the investigation on June 16, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=102172. 15.0 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11592807&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf - Record of email - engine examination observations (item 2, PDF, 4 pages, 2.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11972578&FileExtension=pdf&FileName=ROE%20engine%20exam%20initial-Rel.pdf - Engine run observations (item 3, PDF, 1 page, 78 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11971725&FileExtension=pdf&FileName=Engine%20run%20mechanic%20statement_Redacted-Rel.pdf - Video of engine run (item 4, MOV, 10.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11965255&FileExtension=mov&FileName=video%20of%20engine%20run-Rel.mov - Record of email - regarding carburetor heat (item 5, PDF, 1 page, 115 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11972650&FileExtension=pdf&FileName=ROE%20CFI%20about%20carb%20heat-Rel.pdf - Carburetor icing chart (item 6, PDF, 3 pages, 107 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14000492&FileExtension=pdf&FileName=CE-09-35%20Carburetor%20Icing-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 7, PDF, 1 page, 87 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11965340&FileExtension=pdf&FileName=NTSB%20N4673R%20Release_Redacted-Rel.pdf - On scene photos - courtesy of the FAA (item 8, PDF, 2 pages, 340 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11971495&FileExtension=pdf&FileName=on%20scene%20photos-Rel.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.