# NTSB CEN10LA496: Cessna 182T, N1142U, Mosby, MT, August 18, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 18, 2010, 10:00 local (16:00 UTC) - Place: Mosby, MT - Coordinates: 46.735144, -107.86274 - Nearby events: https://openairdocs.org/map.md?lat=46.7351&lon=-107.8627&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-climb to cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report October 17, 2011 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 77078 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN10LA496 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/77078/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=77078 - Page: https://openairdocs.org/ntsb/CEN10LA496 ## Probable cause A partial loss of engine power for undetermined reasons during an en route climb. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Cessna 182T, 2 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=2072703), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-climb to cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Cessna 182T, 2 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=2072703), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342); cases with it: [Cessna 182T, 2 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=2072703), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Cessna 182T, 17 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=2072703), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The airplane experienced a partial loss of engine power during an en route climb when the engine speed decreased to approximately 600 rpms. The pilot was unable to regain engine power after changing several engine control settings. He elected to perform a forced landing to a rough grass field where the airplane struck a ditch and wire fence. A postaccident examination of the airplane and engine did not identify any anomalies that would have resulted in a partial loss of engine power. ## Factual narrative On August 18, 2010, about 1000 central daylight time, a Cessna 182T, N1142U, received substantial damage on impact with terrain during a forced landing on a field near Mosby, Missouri. The pilot reported that the airplane engine experienced a loss of power to idle power during climb. Visual meteorological conditions prevailed at the time of the accident. The 14 Code of Federal Regulations Part 91 personal flight was operating on an instrument rules flight plan. The pilot and passenger was uninjured. The flight originated from Kansas City International Airport (MCI), Kansas City, Missouri, about 0940 and was en route to Dubuque Regional Airport, Dubuque, Iowa. The pilot stated that he flew the airplane once on a "small trip" after an annual inspection without incident. The second flight since the inspection on the day before the accident was to be from DBQ to MCI to DBQ. The second flight on the day before the accident and flew from DBQ to MCI on an instrument rules flight plan with a filed altitude of 8,000 feet mean sea level (msl). During the second flight, the manifold pressure was "probably" 26 inches and the engine speed would have been in the upper green. He also said that everything was "normal" and in the "green." He said that he sets a climb fuel flow of 15.5 gallons per hour (gph) and leans the fuel flow to about 13 gph after the airplane levels off. About 10-15 minutes after departure from DBQ and at altitude of 8,000 msl, the engine "sputtered" for approximately 5 seconds as if the fuel was "cut-off" and the engine then regained power and operated normally. By the time he turned off the autopilot and established an airspeed of 70 knots, the engine regained power. He was at 8,000 feet for a "few" minutes and the fuel flow was 13 gph, the manifold pressure was about 26 inches, and the engine speed would have been in the upper green, "1,500" revolutions per minute (rpm). He was about 5 nautical miles (nm) from the Monticello Regional Airport (MXO), Monticello, Iowa, at the time of the power loss and decided to divert to that airport where the airplane landed without further incident. It was the first time that he experienced the airplane engine "sputter" since he owned it. He never experienced water contamination in the fuel system. After landing, he taxied to the ramp and performed several run-ups during which he checked the magnetos. The run-ups and magneto checks were reported as "fine." He asked several mechanics at MXO to look at the airplane. They reportedly asked the pilot if he had obtained fuel from a fuel truck to which he responded that he had done so before he departed. The pilot said the he normally had the airplane fueled before it is placed in its hangar but on this trip it had not been. He and the mechanics checked the fuel sumps for contamination and none was noted. They also did a visual inspection of the engine and did not see any anomalies. He started that airplane and performed a run-up. He then performed twotake-off and landings and there were no problems with the airplane or engine. The pilot stated that he preflighted the airplane and checked every fuel sump and did not find any water contamination. He filed for 9,000 feet mean sea level (msl) for the return flight from MCI with an initial clearance altitude of 4,000 feet msl. Everything was normal with the takeoff and climb. He climbed with a fuel flow of about 15.5 gallons per hour and a maximum power setting, which he thought was 26 inches of manifold pressure. He was at 4,000 feet msl for 7-8 minutes. After about 10 minutes, he received a clearance to direct to DBQ and a climb to 9,000 feet msl. About 15 minutes after departure and while climbing through 5,200 feet msl, the engine "sputtered" and went to idle. The engine regained power after about 5 seconds but then was "quickly" lost and was not regained. The engine speed was about 600 revolutions per minute (rpm) and it seemed like the engine was "starving" for fuel. He moved the throttle and mixture controls inward and outward and turned on the electric fuel pump. The engine still did not regain power. He established an airspeed of 70 knots, he notified Kansas City Departure telling them he had an engine problem. The engine speed initially improved while he talked to Kansas City Departure. He decided to attempt a landing at Midwest National Air Center Airport (GPH), Mosby, Missouri, which was about 5 nm away. While flying to GPH, the engine continued to operate with an engine speed of 600-650 rpm. He suspected that the engine was not receiving enough fuel and he tried several ways to increase fuel flow such as adjusting the throttle and mixture in and out several times as well as turning the electric fuel pump on. About 2 nm from GPH, the pilot realized that he would not be able to reach GPH so he performed a forced landing on a grassy, rough, and down sloping pasture lined with trees. During the forced landing, the airplane struck a ditch and collapsed the front landing gear. An examination of the airplane by the Federal Aviation Administration revealed that the air intake/filter and exhaust system were unobstructed. The fuel vent system, fuel sumps, and fuel strainers were unobstructed. Fuel was noted throughout the fuel system. Rotation of the propeller by hand confirmed compression of all cylinders, valve train continuity, and continuity to accessory section. Control continuity of the throttle, propeller, and mixture controls was confirmed. Both magnetos produced a spark through each lead when rotated by hand. The fuel servo, RSA-5AD1, part number 256544-3, serial number 70842810, and flow divider part number 2576564-1, serial number 023346, and engine-driven fuel pump, part number LW-15473, date code 0405, were removed for further testing and examination. Flow bench test results of the fuel servo were reported as within current serviceable limits and no internal leakage was observed. The fuel inlet screen was unobstructed. The fueland air diaphragms were intact and pliable. The fuel diaphragm contained a blue colored tacky residue over an estimated 40 degree sector consistent in color with 100 low lead aviation fuel residue. The flow divider was also tested and no obstructed flow was noted and the internal diaphragm did not stick and was pliable. The flow divider outlet fitting threads that fit into the divider body were wrapped with a white tape consistent in color and thickness of Teflon tape. One of the four fuel servo impact tubes contained a similar blue residue. The National Transportation Safety Board Investigator-In-Charge actuated the fuel pump by hand and no anomalies that would have precluded normal operation were noted. ## Aircraft - Registration: [N1142U](https://openairdocs.org/aircraft/N1142U), registered now, S/N 18281604, built 2005 (OpenAirDocs) - Reported make and model: CESSNA 182T - Registry model: [Cessna 182T](https://openairdocs.org/model/cessna-182t) (registry code 2072703) (OpenAirDocs) - Registry engine: [Lycoming IO-540 series](https://openairdocs.org/engine/lycoming-io-540-series) (registry code 41585, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18281604 - Airframe hours: 974 - Engines: Lycoming IO-540-AB1A5 230 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Pilot - Registered owner: Smooth Air Leasing LLC - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 30, 2010 - Departed: MCI, Kansas City, MO - Destination: DBQ, Dubuque, IA - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 42; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, without waivers/limitations; last flight review April 19, 2009; seat: left; flight hours: 1,165 total, 1,050 in this make and model, 945 as pilot in command, 50 in the last 90 days, 9 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 20° at 3 knots - Visibility: 9 statute miles - Lowest ceiling: 1,200 ft overcast - Temperature: 73 °F, dew point 64 °F - Altimeter: 30.04 inHg - Observed at: MCI ## Docket (9 files) The files NTSB released with the investigation on September 7, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=77078. 2.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 453 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40353014&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Record of Conversation - Pilot (item 2, .PDF, 54 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352971&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20Pilot-Master.PDF - Record of Conversation - FAA (item 3, .PDF, 50 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40353013&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20FAA-Master.PDF - Weather Reports and Records (item 4, .PDF, 103 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352973&FileExtension=.PDF&FileName=Weather%20Reports%20and%20Records-Master.PDF - Maintenance Records (item 5, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352975&FileExtension=.PDF&FileName=Maintenance%20Records-Redacted.PDF - Photo of Fuel Servo Diaphram (item 6, .PDF, 225 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352983&FileExtension=.PDF&FileName=Photo%20of%20Fuel%20Servo%20Diaphram-Master.PDF - Photo of Fuel Servo Impact Tube (item 7, .PDF, 167 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352985&FileExtension=.PDF&FileName=Photo%20of%20Fuel%20Servo%20Impact%20Tube-Master.PDF - Photo of Fuel Servo Fuel Screen (item 8, .PDF, 210 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352987&FileExtension=.PDF&FileName=Photo%20of%20Fuel%20Servo%20Fuel%20Screen-Master.PDF - Flow Divider Components (item 9, .PDF, 177 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352989&FileExtension=.PDF&FileName=Flow%20Divider%20Components-Master.PDF From the NTSB's public API. 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