# NTSB GAA17CA027: Piper PA18, N2791P, Palmer, AK, October 14, 2016 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: October 13, 2016, 16:45 local (Oct 14, 2016, 00:45 UTC) - Place: Palmer, AK - Coordinates: 61.401111, -148.600555 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=61.4011&lon=-148.6006&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report January 18, 2017 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 94230 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA17CA027 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/94230/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=94230 - Page: https://openairdocs.org/ntsb/GAA17CA027 ## Probable cause The airplane's encounter with a depression while the pilot applied excessive braking during the landing roll on a grass airstrip, which resulted in a nose-over. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: surface speed/braking](https://openairdocs.org/ntsb-findings/01062045): Aircraft › Aircraft oper/perf/capability · Incorrect use/operation (probable cause); cases with it: [Piper PA-18A, 3 cases](https://openairdocs.org/ntsb-findings/01062045/cases.md?model=7101804), [All aircraft, 238 cases](https://openairdocs.org/ntsb-findings/01062045/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Piper PA-18A, 13 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7101804), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Runway/land/takeoff/taxi surface: soft surface](https://openairdocs.org/ntsb-findings/03023020): Environmental issues › Physical environment · Effect on operation (probable cause); cases with it: [Piper PA-18A, 1 case](https://openairdocs.org/ntsb-findings/03023020/cases.md?model=7101804), [All aircraft, 264 cases](https://openairdocs.org/ntsb-findings/03023020/cases.md) - [Landing gear system: brake](https://openairdocs.org/ntsb-findings/01023242): Aircraft › Aircraft systems · Incorrect use/operation (probable cause); cases with it: [Piper PA-18A, 1 case](https://openairdocs.org/ntsb-findings/01023242/cases.md?model=7101804), [All aircraft, 297 cases](https://openairdocs.org/ntsb-findings/01023242/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096) (defining event); cases with it: [Piper PA-18A, 5 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=7101804), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis The pilot of the tailwheel equipped airplane reported that while braking during the landing roll on a gravel airstrip the right main tire encountered a ground depression. Subsequently, the airplane nosed over and sustained substantial damage to the right wing lift strut and vertical stabilizer. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. ## Factual narrative The pilot of the tailwheel equipped airplane reported that while braking during the landing roll on a gravel airstrip the right main tire encountered a ground depression. Subsequently, the airplane nosed over and sustained substantial damage to the right wing lift strut and vertical stabilizer. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. ## Aircraft - Registration: [N2791P](https://openairdocs.org/aircraft/N2791P), registered now, S/N 18-4426, built 1955 (OpenAirDocs) - Reported make and model: PIPER PA18 (A) - Registry model: [Piper PA-18A](https://openairdocs.org/model/piper-pa-18a) (registry code 7101804) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18-4426 - Year built: 1955 - Airframe hours: 3409.7 - Engines: LYCOMING O-320-A2B 160 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 13, 2016 - Departed: AQY, GIRDWOOD, AK - Destination: Palmer, AK - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 36; injuries: minor; private; airplane ratings: single-engine land; medical: class 1, without waivers/limitations; last flight review June 27, 2015; seat: front; flight hours: 276.5 total, 219.3 in this make and model, 276.5 as pilot in command, 5.3 in the last 90 days, 3.7 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 230° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 48 °F, dew point 25 °F - Altimeter: 29.32 inHg - Observed at: PAAQ, 18 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 20161013021859A](https://openairdocs.org/incident/20161013021859A), Oct 13, 2016: Piper PA-18A, Palmer, AK, Substantial damage. On landing rollout at the picnic table strip on the knik glacier the aircraft hit a depression. The tail came up and the PIC lost lateral control. She then… ## Other investigations on N2791P (5) 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 ANC20CA041](https://openairdocs.org/ntsb/ANC20CA041), Apr 7, 2020: Piper PA 18A (N2791P), Chickaloon, AK, substantial damage. Probable cause: The pilot's selection of unsuitable terrain for landing, which necessitated a go-around, and her subsequent failure to maintain clearance from rising mountainous terrain. - [NTSB GAA16CA102](https://openairdocs.org/ntsb/GAA16CA102), Dec 21, 2015: Piper PA 18A (N2791P), Girdwood, AK, substantial damage. Probable cause: Fuel contamination resulting in the loss of engine power, a forced landing on a highway, and subsequent right wing impact with highway signage. - [NTSB ANC71DAG54](https://openairdocs.org/ntsb/ANC71DAG54), Nov 26, 1970: Piper PA-18A (N2791P), Pt.Alsworth, AK, substantial damage - [NTSB ANC69D0041](https://openairdocs.org/ntsb/ANC69D0041), Aug 11, 1968: Piper PA-18A (N2791P), Chitina, AK, substantial damage - [NTSB ANC66D0048](https://openairdocs.org/ntsb/ANC66D0048), Aug 15, 1965: Piper PA-18A (N2791P), Soldotna, AK, substantial damage ## Docket (2 files) The files NTSB released with the investigation on December 5, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=94230. 2.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40447042&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Accident Photo (Provider Unknown) (item 2, .PDF, 1 photo, 338 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40447043&FileExtension=.PDF&FileName=Accident%20Photo%20(Provider%20Unknown)-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.