# NTSB CEN14LA476: Piper PA-46-350P, N747TH, Cortez, CO, September 3, 2014 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: September 3, 2014, 12:38 local (18:38 UTC) - Place: Cortez, CO - Coordinates: 37.303054, -108.628051 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=37.3031&lon=-108.6281&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report January 18, 2017 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - Salt Lake City - NTSB case key (mKey): 90011 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN14LA476 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90011/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90011 - Page: https://openairdocs.org/ntsb/CEN14LA476 ## Probable cause The flight instructor’s delayed decision to abort the simulated engine out maneuver, his failure to unfeather the propeller before restoring engine power, and his inadequate airspeed management, which led to an aerodynamic stall at low altitude. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Action: delayed action](https://openairdocs.org/ntsb-findings/02041025): Personnel issues › Action/decision · Instructor/check pilot (probable cause); cases with it: [Piper PA 46-350P, 4 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md?model=7104620), [All aircraft, 894 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Instructor/check pilot (probable cause); cases with it: [Piper PA 46-350P, 40 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7104620), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Propeller system: propeller feather/reversing](https://openairdocs.org/ntsb-findings/01046123): Aircraft › Aircraft propeller/rotor · Incorrect use/operation (probable cause); cases with it: [Piper PA 46-350P, 1 case](https://openairdocs.org/ntsb-findings/01046123/cases.md?model=7104620), [All aircraft, 26 cases](https://openairdocs.org/ntsb-findings/01046123/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: [Piper PA 46-350P, 15 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=7104620), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Use of equip/info: use of equip/system](https://openairdocs.org/ntsb-findings/02063015): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Piper PA 46-350P, 4 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md?model=7104620), [All aircraft, 1,391 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Simulated/training event](https://openairdocs.org/ntsb-events/600); cases with it: [Piper PA 46-350P, 2 cases](https://openairdocs.org/ntsb-events/600/sequence.md?model=7104620), [All aircraft, 173 cases](https://openairdocs.org/ntsb-events/600/sequence.md) - [Landing: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event); cases with it: [Piper PA 46-350P, 11 cases](https://openairdocs.org/ntsb-events/241/sequence.md?model=7104620), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Piper PA 46-350P, 40 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7104620), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The accident occurred during a local instructional flight to satisfy the commercial pilot's annual insurance currency requirements in the accident airplane. The flight instructor reported that the pilot was demonstrating a simulated loss of engine power during initial climb and return for a downwind landing. During initial climb, upon reaching 1,200 ft above ground level (agl), the flight instructor reduced engine power to flight idle and feathered the propeller. In response, the pilot reduced airplane pitch and entered a left, 45-degree-bank turn back toward the airport. The flight instructor stated that, upon rolling wings level, the airplane appeared to be lower than he had expected as it glided toward the runway; however, he believed there was sufficient altitude remaining to safely land on the runway and told the pilot to continue without increasing the engine power. The flight instructor ultimately decided to abort the maneuver as the airplane crossed over the runway threshold at 40 ft agl. The flight instructor advanced the engine power lever to the full-forward position and increased airplane pitch to arrest the descent; however, he did not perceive an increase in engine thrust. Without an increase in engine thrust and with the increased pitch, the airplane's airspeed decreased rapidly, and the airplane entered an aerodynamic stall about 30 ft above the runway. The airplane impacted the runway before sliding into a grassy area. The flight instructor reported that he did not recall advancing the propeller control when he decided to abort the maneuver, and, as such, the perceived lack of engine thrust was likely because the propeller remained feathered after he increased engine power. Additionally, the flight instructor postulated that the airplane's landing gear had not been retracted after takeoff, which resulted in a reduced climb gradient, and, as such, the airplane entered the maneuver farther away from the airport than anticipated. Further, with the landing gear extended, the airplane experienced a reduction in glide performance during the simulated forced landing. The flight instructor reported that the accident could have been prevented if he had maintained a safe flying airspeed after he took control of the airplane. Additionally, he believed that his delayed decision to abort the maneuver resulted in an insufficient margin of safety. ## Factual narrative On September 3, 2014, about 1238 mountain daylight time, a Piper model PA-46-350P airplane, N747TH, was substantially damaged while landing at the Cortez Municipal Airport (CEZ), Cortez, Colorado. The commercial pilot and his flight instructor sustained minor injuries. The airplane was registered to and operated by Philburto Aviation, LTD, under the provisions of 14 Code of Federal Regulations Part 91 without a flight plan. Day visual meteorological conditions prevailed for the local instructional flight, which had departed shortly before the accident.The flight instructor reported that the purpose of the flight was to satisfy the pilot's annual insurance currency requirements in the accident airplane. The flight instructor stated that earlier in the morning they had completed several visual flight rules (VFR) flight maneuvers before deciding to conduct takeoff-and-landings at CEZ. The flight instructor reported that following several uneventful landings, they decided to perform a simulated loss of engine power following a takeoff from runway 21 (7,205 feet by 100 feet, asphalt) and return for a downwind landing on runway 3. During initial climb from runway 21, upon reaching 1,200 feet above ground level (agl), the flight instructor reduced engine power to flight idle and feathered the propeller. In response, the pilot reduced airplane pitch and entered a 45-degree bank left turn back toward the airport. The pilot maintained best-glide airspeed (90 knots) throughout the left turn and rolled wings-level when the airplane was aligned with runway 3. The flight instructor stated that, upon rolling wings level, the airplane appeared to be lower than he had expected as it glided toward the runway; however, he believed there was sufficient altitude remaining to safely land on the runway and told the pilot to continue without an increase in engine power. The flight instructor ultimately decided to abort the maneuver as the airplane crossed over the runway 3 threshold at 40 feet agl. He reported that despite the airplane having sufficient altitude remaining to land on the remaining runway, he thought it would be safer to abort the simulated engine failure and recover under powered-flight. He took control of the airplane, advanced the engine power lever to the full forward position, and increased airplane pitch to arrest the descent; however, he did not perceive an increase in thrust from the engine. Without an increase in engine thrust, the airplane's airspeed decreased rapidly and the airplane entered an aerodynamic stall about 30 feet above the runway. The airplane impacted the runway, about 500 feet from the approach threshold, before it slid off the runway into a grassy area. The flight instructor reported that the engine continued to operate after the accident, and that he secured it by pulling the condition lever to the full aft position. The main wing spar and fuselage were substantially damaged during the impact sequence. The flight instructorreported that he did not recall advancing the propeller control when he decided to abort the maneuver, and as such, the perceived lack of engine thrust was likely because the propeller remained feathered as he increased engine power. Additionally, the flight instructor reported that neither he or the pilot remember extending the landing gear following the simulated engine failure; however, both pilots recalled seeing the landing gear position lights illuminated during the maneuver. The flight instructor postulated that the airplane's landing gear had not been retracted after takeoff, which resulted in a reduced climb gradient due to the additional aerodynamic drag of the extended landing gear, and as such, the airplane entered the maneuver farther away from the airport than anticipated. Furthermore, with the landing gear extended, the airplane experienced a reduction in glide performance during the simulated forced landing. The flight instructor reported that the accident could have been prevented had he maintained a safe flying airspeed after he took control of the airplane. Additionally, the flight instructor believed that his delayed decision to abort the maneuver had resulted in an insufficient margin of safety. At 1253, the CEZ automated surface observing system (ASOS) reported: wind 220 degrees at 12 knots, visibility 10 miles, clear sky, temperature 29 degrees Celsius; dew point 1 degrees Celsius; and an altimeter setting of 30.07 inches of mercury. ## Aircraft - Registration: [N747TH](https://openairdocs.org/deregistered/N747TH-2015-02-09), registration cancelled 2015-02-09, S/N 4636200, built 1999 (OpenAirDocs) - Reported make and model: PIPER PA-46-350P - Registry model: [Piper PA 46-350P](https://openairdocs.org/model/piper-pa-46-350p) (registry code 7104620) (OpenAirDocs) - Registry engine: [Lycoming TIO-540 series](https://openairdocs.org/engine/lycoming-tio-540-series) (registry code 41569, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 4636200 - Year built: 1999 - Airframe hours: 2900 - Engines: Pratt & Whitney PT6A-35 560 horsepower turbo prop - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Philburto Aviation, LTD - Registered owner: Philburto Aviation, LTD - Airworthiness certificate: Standard, Normal - Last inspection: Annual, December 2, 2013 - Departed: CEZ, Cortez, CO - Destination: CEZ, Cortez, CO - Airport: CEZ, Cortez Municipal Airport, runway 03, 7,205 × 100 ft, asphalt - Equipment: Stall warning system, Onboard weather, Electronic primary flight display, Auto-pilot, Electronic multifunction display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 54; injuries: minor; airline transport, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review July 18, 2014; seat: right; restraint: 3-point; flight hours: 4,184 total, 1,648 in this make and model, 3,979 as pilot in command, 63 in the last 90 days, 21 in the last 30 days, 2 in the last 24 hours - Pilot; age 60; injuries: minor; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review August 31, 2013; seat: left; restraint: 3-point; flight hours: 4,000 total, 2,050 in this make and model, 3,917 as pilot in command, 50 in the last 90 days, 29 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 220° at 12 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 84 °F, dew point 34 °F - Altimeter: 30.06 inHg - Observed at: CEZ ## 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 20140903020729A](https://openairdocs.org/incident/20140903020729A), Sep 3, 2014: Piper PA 46-350P, Cortez, CO, Substantial damage. Insurance required recurrent training was being provided. Normal takeoff, with the exception that the landing gear was never retracted (they should have been),… ## Docket (2 files) The files NTSB released with the investigation on November 7, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90011. 997 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 898 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446181&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Weather Reports (item 2, .PDF, 99 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446182&FileExtension=.PDF&FileName=Weather%20Reports-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.