# NTSB WPR11CA387: P&M GT450, N988AZ, Teton Village, WY, August 17, 2011 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Data collection · Final report - Date: August 16, 2011, 18:40 local (Aug 17, 2011, 00:40 UTC) - Place: Teton Village, WY - Coordinates: 43.633609, -110.908607 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.6336&lon=-110.9086&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report October 17, 2011 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration FSDO - NTSB case key (mKey): 81519 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR11CA387 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/81519/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=81519 - Page: https://openairdocs.org/ntsb/WPR11CA387 ## Probable cause The pilot's failure to maintain an adequate airspeed, which resulted in a stall mush to ground impact. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [P&M QUIK GT450 912S, 1 case](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=0600034), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Terrain: mountainous/hilly terrain](https://openairdocs.org/ntsb-findings/03021010): Environmental issues › Physical environment · Decision related to condition (probable cause); cases with it: [P&M QUIK GT450 912S, 1 case](https://openairdocs.org/ntsb-findings/03021010/cases.md?model=0600034), [All aircraft, 329 cases](https://openairdocs.org/ntsb-findings/03021010/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [P&M QUIK GT450 912S, 1 case](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=0600034), [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: [P&M QUIK GT450 912S, 2 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=0600034), [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. - [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [P&M QUIK GT450 912S, 1 case](https://openairdocs.org/ntsb-events/240/sequence.md?model=0600034), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Maneuvering-low-alt flying: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241); cases with it: [P&M QUIK GT450 912S, 1 case](https://openairdocs.org/ntsb-events/241/sequence.md?model=0600034), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [P&M QUIK GT450 912S, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=0600034), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot reported departing the airport in the light-sport weight-shift-control airplane, and flying southbound along the western slopes of the Teton Mountain Range. The airplane climbed to an altitude of about 8,000 feet mean sea level, and the pilot changed course, approaching a canyon area to the east. As he approached rising terrain the airplane's rate of climb began to diminish. He elected to continue flight towards a plateau, due to ridges which were now encroaching from his left and right. He attempted to increase the airplane's rate of climb, and the airspeed subsequently began to decrease. He reported that as the airplane approached stall speed, he encountered a gust of wind and the airplane stalled. He lowered the airplane's nose, and was able recover control about 20 feet above ground level. He attempted to land ahead on the plateau; however, during the landing roll, the nose landing gear collapsed, and the airplane rolled onto the right wing, substantially damaging both wings. The accident site was located in a remote area at the 9,800-foot-level on the western slope of the mountain range. The pilot utilized a SPOT Global Positioning System (GPS) emergency locator to summon assistance from search and rescue personnel, who located him about 2 hours after the accident. The pilot reported no preimpact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation. ## Factual narrative The pilot reported departing the airport in the light-sport weight-shift-control airplane, and flying southbound along the western slopes of the Teton Mountain Range. The airplane climbed to an altitude of about 8,000 feet mean sea level, and the pilot changed course, approaching a canyon area to the east. As he approached rising terrain the airplane's rate of climb began to reduce. He elected to continue flight towards a plateau, due to ridges which were now encroaching from his left and right. He attempted to increase the airplane's rate of climb, and the airspeed subsequently began to decrease. He reported that as the airplane approached stall speed, he encountered a gust of wind and the airplane stalled. He lowered the airplane's nose, and was able recover control about 20 feet above ground level. He attempted to land ahead on the plateau, however during the landing roll, the nose landing gear collapsed, and the airplane rolled onto the right wing. The pilot sustained serious injuries during the accident sequence, and the airplane sustained substantial damage to both wings. The accident site was located in a remote area at the 9,800-foot-level on the western slope of the mountain range. The pilot utilized a SPOT Global Positioning System (GPS) emergency locator to summon assistance from search and rescue personnel, who located him about 2 hours after the accident. The pilot reported no preimpact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation. ## Aircraft - Registration: [N988AZ](https://openairdocs.org/deregistered/N988AZ-2013-05-28), registration cancelled 2013-05-28, S/N 8270, built 2007 (OpenAirDocs) - Reported make and model: P&M Aviation GT450 - Registry model: [P&M QUIK GT450 912S](https://openairdocs.org/model/p-m-quik-gt450-912s) (registry code 0600034) (OpenAirDocs) - Registry engine: [Rotax 912ULS series](https://openairdocs.org/engine/rotax-912uls-series) (registry code 55572, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: 8270 - Airframe hours: 142 - Engines: Rotax 912ULS 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Special light-sport (Special) - Last inspection: Annual, May 11, 2011, 142 hours before - Departed: KDIJ, Driggs, ID - Destination: KDIJ, Driggs, ID - Airport: KDIJ, Driggs ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 57; injuries: serious; sport pilot; airplane ratings: single-engine land; medical: sport pilot; seat: front; flight hours: 236 total, 130 in this make and model, 134 as pilot in command, 28 in the last 90 days, 4 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 280° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 73 °F, dew point 27 °F - Altimeter: 30.22 inHg - Observed at: KDIH, 12 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 20110816022029A](https://openairdocs.org/incident/20110816022029A), Aug 16, 2011: P&M Aviation Ltd QUIK GT450 912S, Jackson, WY, Substantial damage. The light sport, weight shift aircraft was being operated on a personal flight, in a mountainous area above 9000 feet asl. While attempting to fly over a peak… ## Docket (3 files) The files NTSB released with the investigation on September 8, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=81519. 3.9 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40353657&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - FAA Image of Accident Site (item 2, .PDF, 1 photo, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40353567&FileExtension=.PDF&FileName=FAA%20Image%20of%20Accident%20Site-Master.PDF - Photo 1: Airplane Damage (item 3, .PDF, 120 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40353568&FileExtension=.PDF&FileName=Photo%201%3A%20Airplane%20Damage-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.