# NTSB ANC16CA066: Piper PA 18, N5773D, McGrath, AK, September 18, 2016 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: September 18, 2016, 13:00 local (21:00 UTC) - Place: McGrath, AK - Coordinates: 63.380001, -156.36 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=63.3800&lon=-156.3600&mi=10 - Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping) - Defining event: [Taxi: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 5, 2016 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration - NTSB case key (mKey): 94036 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC16CA066 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/94036/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=94036 - Page: https://openairdocs.org/ntsb/ANC16CA066 ## Probable cause The pilot's excessive taxi speed, which resulted in a loss of control and subsequent nose over. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Piper PA-18, 21 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7101802), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters: surface speed/braking](https://openairdocs.org/ntsb-findings/01062045): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Piper PA-18, 4 cases](https://openairdocs.org/ntsb-findings/01062045/cases.md?model=7101802), [All aircraft, 238 cases](https://openairdocs.org/ntsb-findings/01062045/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Taxi: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Piper PA-18, 17 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=7101802), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Taxi: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Piper PA-18, 16 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=7101802), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) - [Taxi: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Piper PA-18, 19 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7101802), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot had landed his tailwheel-equipped airplane on a rough and uneven, soft, off-airport landing site in gusty wind conditions. He reported that he had landed at the same spot the previous day, but at a higher gross weight. While back taxiing the airplane became stuck, he applied near full power and the airplane began to roll. In an effort to avoid becoming stuck again, he chose to taxi at a higher than normal speed and power setting. He stated that the airplane began to accelerate and in an effort to slow down, he applied the main wheel brakes while simultaneously hitting a large tussock. The airplane nosed over sustaining substantial damage to the rudder and vertical stabilizer. The pilot stated that there were no preaccident mechanical anomalies that would have precluded normal operation. In the recommendation section of the NTSB Accident/Incident Reporting Form 6120.1, the pilot stated that the accident may have been prevented if he had shut down the airplane and walked the landing zone prior to taxi to look for hazards, or if he had a better understanding of how gross weight affects airplane control while on the ground. ## Factual narrative The pilot had landed his tailwheel-equipped airplane on a rough and uneven, soft, off-airport landing site in gusty wind conditions. He reported that he had landed at the same spot the previous day, but at a higher gross weight. While back taxiing the airplane became stuck, he applied near full power and the airplane began to roll. In an effort to avoid becoming stuck again, he chose to taxi at a higher than normal speed and power setting. He stated that the airplane began to accelerate and in an effort to slow down, he applied the main wheel brakes while simultaneously hitting a large tussock. The airplane nosed over sustaining substantial damage to the rudder and vertical stabilizer. The pilot stated that there were no preaccident mechanical anomalies that would have precluded normal operation. In the recommendation section of the NTSB Accident/Incident Reporting Form 6120.1, the pilot stated that the accident may have been prevented if he had shut down the airplane and walked the landing zone prior to taxi to look for hazards, or if he had a better understanding of how gross weight affects airplane control while on the ground. ## Aircraft - Registration: [N5773D](https://openairdocs.org/aircraft/N5773D), registered now, S/N 18-5275, built 1956 (OpenAirDocs) - Reported make and model: PIPER PA 18 (105SPECIAL) - Registry model: [Piper PA-18](https://openairdocs.org/model/piper-pa-18) (registry code 7101802) (OpenAirDocs) - Registry engine: [Continental C90 series](https://openairdocs.org/engine/continental-c90-series) (registry code 17009, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18-5275 - Year built: 1956 - Airframe hours: 5321 - Engines: Lycoming O-360 A2A 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, August 21, 2016 - Destination: McGrath, AK - Equipment: Electronic primary flight display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 36; injuries: none; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review July 6, 2016; seat: front; restraint: 4-point; flight hours: 751 total, 650 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 300° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: 5,000 ft overcast - Temperature: 46 °F, dew point 39 °F - Altimeter: 30.02 inHg - Observed at: PAMC ## 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 20160918021169A](https://openairdocs.org/incident/20160918021169A), Sep 18, 2016: Piper PA-18, Mc Grath, AK, Substantial damage. On 09/19/2016 @ approximately 1230 AKDT the airman landed N5773D in gusty wind conditions on rough but soft terrain 60 miles wnw of mcgrath AK. He positioned… ## Other investigations on N5773D (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 ANC09CA096](https://openairdocs.org/ntsb/ANC09CA096), Sep 5, 2009: Piper PA-18 (N5773D), Fairbanks, AK, substantial damage. Probable cause: The pilot’s decision to land on unsuitable terrain, which resulted in a loss of control and a collision with trees. ## Docket (1 files) The files NTSB released with the investigation on October 6, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=94036. 1.9 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40445136&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-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.