# NTSB ANC24FA085: Piper PA-18-150, N7154Z, McGrath, AK, August 31, 2024 - Type: NTSB accident investigation - Classification: Accident · Fatal · Class 3 · Field · Final report - Date: August 31, 2024, 10:00 local (18:00 UTC) - Place: McGrath, AK · south of McGrath - Coordinates: 62.008135, -154.80312 - Nearby events: https://openairdocs.org/map.md?lat=62.0081&lon=-154.8031&mi=10 - Phase of flight: [Unknown](https://openairdocs.org/ntsb-phases/990) (OpenAirDocs' grouping) - Defining event: [Unknown: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Alaska Regional Office - Parties: Piper, FAA - NTSB case key (mKey): 195031 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC24FA085 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/195031/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=195031 - Page: https://openairdocs.org/ntsb/ANC24FA085 ## Probable cause The pilot's exceedance of the airplane’s critical angle of attack while maneuvering for landing, which resulted in an aerodynamic stall and loss of control. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible (probable cause); cases with it: [Piper PA-18-150, 24 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=7101828), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/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-18-150, 160 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7101828), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Unknown: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event); cases with it: [Piper PA-18-150, 11 cases](https://openairdocs.org/ntsb-events/241/sequence.md?model=7101828), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) ## Analysis The airplane departed from a remote hunting camp and traveled to a 2,500-ft ridge about 3.5 miles away to drop off supplies to a hunting guide; the pilot was planning to continue to an airport for fuel. According to the guide who was at the scene of the accident, the airplane flew over their camp several times before flying further up the ridge, where it executed several passes over the ridge. While the pilot had landed on this ridge in seasons past, this would have been his first time landing on the ridge this year. The guide reported that winds near the accident site were about 15 mph from the northeast and the visibility was good. He reported that the airplane was traveling slow and low on a southwest heading and began a right turn to the northeast. As the airplane began what the guide thought to be a right base to final turn, he lost sight of the airplane. However, the guide reported that he could still hear the airplane’s engine. He reported hearing the engine “call for a lot of power” twice and a few seconds later he heard the airplane impact the ground. The airplane was found nose down in a near-vertical attitude on a northeast heading on the south side of the ridge. The wings remained partially attached and the tail was bent slightly to the right. The wreckage pattern of the airplane was consistent with the airplane impacting the ground during a stall/spin. The pilot and owner of the accident airplane had incorporated modifications to the airplane, including leading edge slats and slotted two-piece flaps. The leading edge slats were removed a few months before the accident. Although these modifications allowed for lower airspeeds during landing and altered the stall characteristics of the airplane, the investigation was not able to determine if the changed flight characteristics might have played a role in the experienced pilot’s exceedance of the airplane’s critical angle of attack while maneuvering. A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. Based on the available information, it is likely that the pilot exceeded the airplane’s critical angle of attack while maneuvering for landing, which resulted in an aerodynamic stall and loss of control. ## Factual narrative On August 31, 2024, about 1000 Alaska daylight time, a Piper PA-18-150 airplane, N7154Z, sustained substantial damage when it was involved in an accident near McGrath, Alaska. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 business flight. The airplane departed from a remote hunting camp and traveled to a 2,500-ft ridge about 3.5 miles away to drop off supplies to a hunting guide; the pilot was planning to continue to McGrath for fuel. According to the guide who was at the scene of the accident, the airplane flew over their camp several times before flying further up the ridge, where it executed several passes over the ridge. While the pilot had landed on this ridge in seasons past, this would have been his first time landing on the ridge this season. The guide reported that winds near the accident site were about 15 mph from the northeast and the visibility was good. He reported that the airplane was traveling slow and low on a southwest heading and then it began a right turn to the northeast. As the airplane began what the guide thought to be a right base to final turn, he lost sight of the airplane. However, the guide reported that he could still hear the airplane’s engine. He reported hearing the engine “call for a lot of power” twice and a few seconds later he heard the airplane impact the ground. The airplane was found nose down in a near-vertical attitude on a northeast heading on the south side of the ridge. The wings remained partially attached and the tail was bent slightly to the right. Based on witness statements, as well as pictures and videos from the pilot’s website, the accident airplane previously had leading edge slats and slotted two-piece flaps installed from 2020 until sometime in 2023-2024 (see Figures 1, 2). The bolt pattern observed on the leading edges of the accident airplane’s wings resembled that of the Mackey Slats (see Figure 3). However, engine and airframe logbooks could not be located so exact details were not available. Leading edge slats and slotted two-piece flaps change the flight characteristics of a conventional airplane by reducing the maneuvering speed. There is currently no Supplemental Type Certificates (STCs) for leading edge slats; therefore, airplanes with these installed are not approved for passenger-carrying operations. The FAA was notified in October 2022 that the pilot may have been flying passengers in the accident airplane with the leading edge slats installed, and the FAA contacted the pilot regarding the installation of the leading edge slats. The pilot reported that he was helping a manufacturer obtain an STC for the leading edge slats and denied flying passengers with leading edge slats installed. The pilot/owner removed the leading edge slats sometime in the spring of 2024, after his interaction with the FAA. A postaccident examination of the airframe and engine revealed no preaccident mechanical malfunctions or failures with theairplane that would have precluded normal operation. Figure 1 Accident airplane with slotted two-piece flaps and leading edge slats Figure 2 Accident airplane with leading edge slats Figure 3 Leading edge slat attachment points on wing of accident airplane ## Aircraft - Registration: [N7154Z](https://openairdocs.org/aircraft/N7154Z), registered now, S/N 18-8268, built 1965 (OpenAirDocs) - Reported make and model: PIPER PA-18-150 - Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18-8263 - Year built: 1965 - Engines: Lycoming O-360 180 horsepower reciprocating - Damage: Substantial damage - Flight: Business, Part 91 - Airworthiness certificate: Standard, Normal - Departed: Remote base camp airstrip, AK - Destination: Same as departure ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 58; injuries: fatal; commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; medical: class 2, with waivers/limitations; seat: front; restraint: 4-point; toxicology performed; flight hours: 4,269 total ## Weather - Conditions: Visual (VMC), Day - Wind: 360° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 50 °F, dew point 45 °F - Altimeter: 29.73 inHg - Icing: Unknown - Observed at: PAMC, 61 nm away - METAR: PAMC 311753Z 36005KT 10SM CLR 10/07 A2973 RMK AO2 SLP071 T01000072 10100 20050 50000 $ ## 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 20240831013089A](https://openairdocs.org/incident/20240831013089A), Aug 31, 2024: Piper PA-18-150, Mcgrath, AK, Substantial damage, 1 fatal. The airplane departed from a remote hunting base camp at about 0930 and traveled to a 2,500 ft. ridge about 2.5 miles away to drop off supplies to hunting… ## Other investigations on N7154Z (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 ANC12LA075](https://openairdocs.org/ntsb/ANC12LA075), Jul 14, 2012: Piper PA-18-150 (N7154Z), Kenai, AK, substantial damage. Probable cause: The in-flight separation of a propeller tip due to an unauthorized and undocumented propeller repair. ## Docket (10 files) The files NTSB released with the investigation on August 20, 2025, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=195031. 7.9 MB in all. - Memorandum of record-witness interview (item 1, PDF, 2 pages, 69 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18295269&FileExtension=pdf&FileName=MOR%20Perry%20Raber-Rel.pdf - Electronic device email report datatoys camera (item 2, PDF, 4 pages, 404 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18052920&FileExtension=pdf&FileName=ANC24FA85%20Recorders%20email%20data%20toys_Redacted-Rel.pdf - Electronic device email report ei instruments (item 3, PDF, 3 pages, 341 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18175375&FileExtension=pdf&FileName=EI%20Email%20ANC24FA085_Redacted-Rel.pdf - Recorders email avmap GPS (item 4, PDF, 3 pages, 748 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18348390&FileExtension=pdf&FileName=ANC24FA085%20Recorder%20email%20AVMAP%20GPS_Redacted-Rel.pdf - Wreckage examination (item 5, PDF, 22 pages, 3.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19056351&FileExtension=pdf&FileName=ANC24FA085%20wreckage%20exam-Rel.pdf - Evidence control form (item 6, PDF, 2 pages, 943 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18442787&FileExtension=pdf&FileName=evidence%20control%20form_Redacted-Rel.pdf - Certification of party representive (item 7, PDF, 10 pages, 186 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18410847&FileExtension=pdf&FileName=Piper%20Certification%20of%20Party%20Representative%20%20N7145Z_Redacted-Rel.pdf - Release of wreckage (item 8, PDF, 3 pages, 153 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18346952&FileExtension=pdf&FileName=Wreckage%20Release%207154Z_Redacted-Rel.pdf - Toxicological report (item 9, PDF, 1 page, 441 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18174956&FileExtension=pdf&FileName=Toxicology%20ANC24FA085_Redacted-Rel.pdf - Photos (item 10, PDF, 4 pages, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18274942&FileExtension=pdf&FileName=Investigative%20Photographs%20ANC24FA085-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.