# NTSB CHI05FA162: Piper PA-46-310P, N4386G, Grand Rapids, MN, July 4, 2005 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: July 4, 2005, 17:58 local (22:58 UTC) - Place: Grand Rapids, MN - Coordinates: 47.211112, -93.509719 - Nearby events: https://openairdocs.org/map.md?lat=47.2111&lon=-93.5097&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report December 28, 2006 - Report: Approved by Office Director - Parties: Teledyne Continental Motors, Kelly Aerospace, The New Piper Aircraft, Inc., Hartzell Propellers, Federal Aviation Administration - NTSB case key (mKey): 61855 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI05FA162 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/61855/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=61855 - Page: https://openairdocs.org/ntsb/CHI05FA162 ## Probable cause An observed loss of engine power due to the bound/jammed turbocharger wastegate during takeoff, the pilot not maintaining airplane control, and the stall he inadvertently encountered. A factor was the maintenance personnel not replacing the turbocharger wastegate bypass valve assembly during the last annual inspection 8.7 hours of operation prior to the accident. An additional factor was the manufacturer's insufficiently defined inspection conditions for the bypass valve's proper operation. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, takeoff - maintenance,replacement - not performed, other maintenance personnel (contributing factor) - condition(s)/step(s) insufficiently defined, manufacturer (contributing factor) - exhaust system,wastegate - jammed (cause) - condition(s)/step(s) not listed, manufacturer - Loss of control - in flight, emergency landing after takeoff - aircraft control - not maintained, pilot in command (cause) - procedures/directives - not followed, pilot in command (cause) - airspeed - not maintained, pilot in command - stall - inadvertent, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis The airplane was destroyed on impact with terrain during a forced landing following an observed in-flight loss of engine power after takeoff. A witness observed the takeoff and stated that the airplane took off from the end of runway 34. About halfway down the runway the airplane emitted a sound like a rapid misfire, a pop, and then no more audible engine sounds. The airplane was about 300 to 400 feet above ground level at that point. He said that the airplane turned right then turned left to a bank where the wing was straight down. The airplane's wings then leveled, the airplane descended, and it impacted terrain. He stated that the time from the sounds to the impact was about two to three seconds. An on-scene examination revealed no airframe pre-impact anomalies. An engine examination revealed a cracked crankshaft propeller flange. The engine without the turbochargers and with the original crankshaft was test run up to 2,100 RPM. A propeller and governor inspection revealed no anomalies. Examination of the turbocharger system's exhaust bypass valve assembly revealed its butterfly valve was stuck (bound) in the extended closed position. The engine's cracked crankshaft was removed and a serviceable crankshaft was installed. The engine was test run again with a serviceable exhaust bypass valve assembly. The engine produced rated power. The original exhaust bypass valve assembly was reinstalled. The exhaust bypass valve assembly's wastegate bound again during an engine run and a loss of engine power was observed. Sectioning of the bypass valve assembly revealed a bent wastegate shaft. The valve assembly lever arm was bent and exhibited pre-impact toolmarks consistent with pliers loosening a bound wastegate shaft. The airplane's pilot operating handbook and Federal Aviation Administration (FAA) approved airplane flight manual (POH), in part, stated, "ENGINE POWER LOSS DURING TAKEOFF If sufficient runway remains for a normal landing, leave gear down and land straight ahead." The engine manufacturer's maintenance and operator's manual stated that the wastegate is required to be checked for operation and condition during 100 hour inspections. The manual did not specify a procedure for maintenance personnel on how to check the wastegate's operation and its acceptable condition. National Transportation Safety Board Recommendation A-94-081, issued to the FAA in 1994, stated, "Require the amendment of pilot operating handbooks and airplane flight manuals applicable to aircraft equipped with engine turbochargers by including in the 'Emergency Procedures' section information regarding turbocharger failure. The information should include procedures to minimize potential hazards relating to fire in flight and/or loss of engine power." The airplane's POH latest revision was dated October 14, 2002 and review of the emergency procedures section showed that the POH did not contain information, procedures, or amplified procedures on turbocharger failures. The airplane accumulated 8.7 hours of operation since the last annual inspection. ## Factual narrative HISTORY OF FLIGHT On July 4, 2005, about 1758 central daylight time, a Piper PA-46-310P, N4386G, piloted by a private pilot, was destroyed on impact with terrain during a forced landing following an observed in-flight loss of engine power after takeoff from runway 34 at the Grand Rapids/Itasca County Airport-Gordon Newstrom Field (GPZ), near Grand Rapids, Minnesota. The personal flight was operating under 14 Code of Federal Regulations Part 91. No flight plan was on file. The pilot sustained fatal injuries. The flight was originating at the time of the accident and its destination was unknown. A witness located at GPZ observed the takeoff and stated that the airplane took off from the end of runway 34. About halfway down the runway the airplane emitted a sound like a rapid misfire, a pop, and then no more audible engine sounds. The airplane was about 300 - 400 feet above ground level at that point. He said that the airplane turned right then turned left to a bank where the wing was straight down. The airplane's wings then leveled, the airplane descended, and it impacted terrain. He stated that the time from the sounds to the impact was about two to three seconds. PERSONNEL INFORMATION The pilot held a private pilot certificate with airplane single-engine land and instrument airplane ratings. Federal Aviation Administration (FAA) records show that the pilot's last medical examination was completed on June 22, 2005, when he was issued a third-class medical certificate with the limitation that he shall possess glasses that correct for near vision. On the application for that medical certificate, the pilot reported that he had accumulated 2,200 hours of total flight time. He reported that he had accumulated 50 hours of flight time in the six months prior to that medical certificate application. The pilot obtained flight instruction for the PA-46-310P from Simcom. Their training records showed that the pilot's last endorsement for a flight review was on July 1, 2004. AIRCRAFT INFORMATION N4386G, a 1985 Piper PA-46-310P, Malibu, serial number 46-8508037, was an all-metal airplane with semimonocoque fuselage and empennage construction. The airplane was powered by a six-cylinder, horizontally opposed, turbocharged, air cooled, fuel injected, Teledyne Continental Motors (TCM) TSIO-520-BE(1), serial number 528503, engine. The airplane's propeller was a two-bladed Hartzell BHC-C2YF-1BF model. The airplane was equipped with a pressurized cabin, wing flaps, spoilers, a constant speed propeller, and retractable tricycle landing gear. The airplane had a maximum seating capacity of six occupants, to include two cockpit positions and four cabin positions. The airplane has a certified maximum takeoff weight of 4,100 lbs. The pilot's operating handbook and FAA approved airplane flight manual (POH), in part, stated: Turbocharging is accomplished by two Garrett - A.I.D. turbocompressors, one located on each side of the engine. Turbochargers extract energy from engine cylinder exhaust gases and use this energy to compress engine induction air. This allows the engine to maintain rated power at altitude. When engine induction air is compressed by the turbocharger, the air temperature is increased. The elevated air temperature is reduced by air aftercoolers located on each side of the engine. This aids in engine cooling and improves engine power and efficiency. Each turbocharger extracts exhaust energy from its respective bank of cylinders to pressurize the induction air. Air flows through the induction inlet louvers into the induction air box, where it is filtered and divided for distribution to the left and right turbo compressors. At the compressor, air pressure and temperature are increased. Pressure increases air density making a greater mass of air available to the engine cylinders on each intake stroke. Air then flows through an aftercooler where air temperature is reduced, further increasing the density of air available to each cylinder. Downstream the aftercoolers, air flow joins at the "Y" junction of intake tubes on the top front of the engine, then passes the throttle butterfly valve and is divided to individual intake pipes flowing to each cylinder. Metered fuel is injected into the cylinder head, upstream of the intake valve. After the fuel burns in the cylinder, exhaust gases flow into the exhaust manifold and then to turbocharger turbines where exhaust energy is extracted to drive the compressor. Turbo compressed air is throttled across the throttle butterfly valve as set by the throttle lever. A sloped control system monitors pressure differential and uses engine oil pressure to automatically position the waste gate valve. The waste gate bleeds excess exhaust gas from the exhaust manifold crossover pipe and out the left exhaust stack, bypassing the turbocharger. Thus the controller automatically maintains manifold pressure. The engine is well protected against overboost damage from excessive manifold pressure. The waste gate controller senses manifold pressure and will continually adjust turbocharger output, maintaining the manifold pressure set by the throttle. The controller automatically protects the engine from overboost damage by limiting manifold pressure to 38 in. Hg. In the event of a controller malfunction, there is a pressure relief valve on the induction manifold which will relieve manifold pressure at 42 in. Hg. Manifold pressure limits can be exceeded with full throttle operation during certain off standard ambient conditions and low engine oil temperature. During such conditions limit manifold pressure to 38 in. Hg maximum. Aircraft logbooks show that the last annual inspection was performed on May 6, 2005. The aircraft had accumulated a total time of 1,847.7 hours at the time of that annual inspection. The airplane's POH, in part, stated: ENGINE POWER LOSS DURING TAKEOFF If sufficient runway remains for a normal landing, leave gear down and land straight ahead. If area ahead is rough, or if it is necessary to clear obstructions: Landing gear selector .............................. UP METEOROLOGICAL INFORMATION At 1755, the recorded GPZ weather was: Wind 290 degrees at 11 knots gusting to 17 knots; visibility 10 statute miles; sky condition few 8,000 feet; temperature 21 degrees C; dew point 12 degrees C; altimeter 29.94 inches of mercury. AIRPORT INFORMATION The North Central US Region Airport/Facility Directory (A/FD) indicated that the airport elevation at GPZ was 1,355 feet above mean sea level (MSL). GPZ was an uncontrolled airport with two runways, 10/28 and 16/34. The A/FD stated that runway 16/34 was 5,755 feet long and 100 feet wide. That runway's surface was composed of asphalt. WRECKAGE AND IMPACT INFORMATION The airplane fuselage came to rest upright northwest of the departure end of runway 34 at latitude 47 degrees 13.018 minutes North and longitude 93 degrees 30.918 minutes West. A ground scar, about 150 feet long with a 287 degrees magnetic heading, was observed. A radio antenna was found at the start of the scar. The airplane's propeller was detached from the engine propeller flange and was found about 135 feet from the start of the ground scar. The right wing was detached from the fuselage and was found near the end of the ground scar about 150 feet from the start of the scar. The airplane fuselage was about 168 feet from the start of the scar and the fuselage was orientated approximately on a 354-degree magnetic heading. An on-scene examination was conducted. The propeller blades were marked A and B. The propeller blade marked with a "B" exhibited an s-shaped bend. Both propeller blades exhibited chordwise abrasion. The inboard section of the detached right wi ## Aircraft - Registration: [N4386G](https://openairdocs.org/deregistered/N4386G-2018-01-19), registration cancelled 2018-01-19, S/N 46-8508037, built 1985 (OpenAirDocs) - Reported make and model: Piper PA-46-310P - Registry model: [Piper PA-46-310P](https://openairdocs.org/model/piper-pa-46-310p) (registry code 7104605) (OpenAirDocs) - Registry engine: [Continental TSIO-520 series](https://openairdocs.org/engine/continental-tsio-520-series) (registry code 17040, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 46-8508037 - Airframe hours: 1856.4 - Engines: Teledyne Continental TSIO-520-BE1 310 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Stephen D. Jensen - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 1, 2005, 8.7 hours before - Departed: GPZ, Grand Rapids, MN - Destination: FCM, MINNEAPOLIS, MN - Airport: GPZ, Grand Rapids/Itasca Co-Gordon, runway 34, 5,755 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; injuries: fatal; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review July 1, 2004; seat: left; toxicology performed; flight hours: 2,200 total ## Weather - Conditions: Visual (VMC), Day - Wind: 290° at 11 knots, gusting 17 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 70 °F, dew point 54 °F - Altimeter: 29.94 inHg - Observed at: GPZ ## 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 20050704034059A](https://openairdocs.org/incident/20050704034059A), Jul 4, 2005: Piper PA46310P, Grand Rapids, MN, Destroyed, 1 fatal. (-23) Aircraft took off from runway 34 and reached an altitude of approximately 300 feet. Witness reported there was a backfire and loss of engine noise.… ## Other investigations on N4386G (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 DEN03LA123](https://openairdocs.org/ntsb/DEN03LA123), Jul 6, 2003: Piper PA-46-310P (N4386G), Englewood, CO, substantial damage. Probable cause: the pilot's improper flare which resulted in a hard landing. Contributing factors were the out-of-calibration waste gate actuator, a blown tire, and the airport sign. ## Docket (21 files) The files NTSB released with the investigation on October 6, 2006, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=61855. 32.0 MB in all. - Record of Interview (item 1, .PDF, 29 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265183&FileExtension=.PDF&FileName=Record%20of%20Interview-Master.PDF - Teledyne Continental Motors Report (item 2, .PDF, 18.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265192&FileExtension=.PDF&FileName=Teledyne%20Continental%20Motors%20Report-Master.PDF - Hartzell Propeller Report (item 3, .PDF, 2.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265193&FileExtension=.PDF&FileName=Hartzell%20Propeller%20Report-Master.PDF - Kelly Aerospace's Reports (item 4, .PDF, 288 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265204&FileExtension=.PDF&FileName=Kelly%20Aerospace%27s%20Reports-Master.PDF - Airplane Description From POH (item 5, .PDF, 577 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265206&FileExtension=.PDF&FileName=Airplane%20Description%20From%20POH-Master.PDF - Piper Maintenance Manual Excerpt (item 6, .PDF, 617 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265208&FileExtension=.PDF&FileName=Piper%20Maintenance%20Manual%20Excerpt-Master.PDF - Teledyne Continental Motors Maintenance & Operator's Manual Excerpt (item 7, .PDF, 301 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265209&FileExtension=.PDF&FileName=Teledyne%20Continental%20Motors%20Maintenance%20%26%20Operator%27s%20Manual%20Excerpt-Master.PDF - Teledyne Continental Motor's Overhaul Manual Excerpts (item 8, .PDF, 87 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265210&FileExtension=.PDF&FileName=Teledyne%20Continental%20Motor%27s%20Overhaul%20Manual%20Excerpts-Master.PDF - Annual Inspection (item 9, .PDF, 148 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265211&FileExtension=.PDF&FileName=Annual%20Inspection-Master.PDF - AF Fuels Lab Report (item 10, .PDF, 31 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265212&FileExtension=.PDF&FileName=AF%20Fuels%20Lab%20Report-Master.PDF - Flight Review & Instrument Competency Endorsements (item 11, .PDF, 30 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265215&FileExtension=.PDF&FileName=Flight%20Review%20%26%20Instrument%20Competency%20Endorsements-Master.PDF - Toxicological Report (item 12, .PDF, 50 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265216&FileExtension=.PDF&FileName=Toxicological%20Report-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 13, .PDF, 228 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265217&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 14, .PDF, 67 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265218&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Master.PDF - Photo 1. Accident Site (item 15, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265366&FileExtension=.PDF&FileName=Photo%201.%20%20Accident%20Site-Master.PDF - Photo 2. Right Wing (item 16, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265367&FileExtension=.PDF&FileName=Photo%202.%20%20Right%20Wing-Master.PDF - Photo 3. Ground Scar (item 17, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265368&FileExtension=.PDF&FileName=Photo%203.%20%20Ground%20Scar-Master.PDF - Photo 4. Removed Spark Plugs (item 18, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265369&FileExtension=.PDF&FileName=Photo%204.%20%20Removed%20Spark%20Plugs-Master.PDF - Photo 5. Waste Gate Assembly (item 19, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265370&FileExtension=.PDF&FileName=Photo%205.%20%20Waste%20Gate%20Assembly-Master.PDF - Photo 6. Lever Arm With Toolmarks (item 20, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265371&FileExtension=.PDF&FileName=Photo%206.%20%20Lever%20Arm%20With%20Toolmarks-Master.PDF - Photo 7. Waste Gate Assembly Shroud (item 21, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40265372&FileExtension=.PDF&FileName=Photo%207.%20%20Waste%20Gate%20Assembly%20Shroud-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.