# NTSB WPR13LA224: Cessna 172M, N20800, Lakeport, CA, April 29, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 29, 2013, 12:15 local (19:15 UTC) - Place: Lakeport, CA - Coordinates: 38.987499, -122.900558 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.9875&lon=-122.9006&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: 1 uninjured - Status: Completed, report September 30, 2014 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Adminstration FSDO - NTSB case key (mKey): 86857 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR13LA224 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/86857/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=86857 - Page: https://openairdocs.org/ntsb/WPR13LA224 ## Probable cause Loss of engine power during climb due to a failure of the No. 2 piston assembly; the reason for the failure could not be determined because of the extent of damage to the piston assembly. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip eng cyl section](https://openairdocs.org/ntsb-findings/01058530): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Cessna 172M, 6 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=2072418), [All aircraft, 373 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md) - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Cessna 172M, 16 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=2072418), [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 172M, 16 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=2072418), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Enroute-climb to cruise: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Cessna 172M, 19 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=2072418), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Emergency descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Cessna 172M, 100 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=2072418), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis During the initial climb following takeoff, the engine began to make a rumbling sound. The pilot began a series of troubleshooting steps, and a short time later, the engine lost all power. The pilot performed a forced landing into a vineyard, where the airplane sustained substantial damage to both wings and the horizontal stabilizer. Examination of the engine revealed catastrophic internal failure focused primarily in the area of the No. 2 piston. Following the failure, excessive heat developed within the engine, which caused the crankshaft to expand and impinge on the oil pump, which in turn failed. The damage sustained to the piston, connecting rod bearing, and connecting rod bolts, prevented an accurate assessment of the failure mode. ## Factual narrative On April 29, 2013, about 1215 Pacific daylight time, a Cessna 172M, N20800, landed in a vineyard near Lakeport, California, following a loss of engine power. The airplane was registered to Air Ward, Inc., and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91. The commercial pilot was not injured, and the airplane sustained substantial damage. The local flight departed Lampson Field Airport, Lakeport, California, about 1200. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported performing an uneventful preflight check, engine run-up, and departure. During the initial climb to 4,000 feet, the engine began to make a rumbling sound, and its speed reduced to about 1,800 rpm. The pilot adjusted the fuel mixture control, and confirmed the fuel selector valve was set to both tanks; however, the airplane would not maintain the climb. He subsequently turned the airplane back towards Lampson Field, and about 3 minutes after the initial anomaly, the engine lost all power. The pilot set the airplane's airspeed to best glide, and performed a forced landing into a vineyard. The airplane struck a trellis, and sustained substantial damage to both wings and the horizontal stabilizer. Engine Examination The engine was removed and examined. The sump contained about 5 quarts of black-colored oil; the oil filter was free of visible particles, and about 1/4 of the oil screen surface was covered in black debris. External examination revealed that while the engine could be rotated by hand at the propeller hub, rotation required an unusually large amount of force. The valves and pistons for cylinders 1, 3, and 4 moved appropriately, and "thumb compression" was attained for those cylinders after the removal of the lower spark plugs. No movement was observed to any of the components for cylinder two. The engine was partially disassembled, revealing that piston number two had become seized within the cylinder head. The connecting rod displayed pink discoloration and remained connected to the crankshaft, but had sheared at the small end, obliterating its connection to the piston pin. The engine sump contained pulverized fragments of piston and rod material, connecting rod bearing, and connecting rod bolts. Both the number 1 piston rod and the crankshaft in the area of the number 1 and 2 connecting rods were dry, and displayed discoloration consistent with excessive heat. Engine Lubrication System Engine oil for the O-320-E2D series engine is circulated under pressure via a meshed spur-gear pump, housed on the accessory case at the rear of the engine. The pump is mounted in-line with, and driven directly by, the crankshaft via its input coupling. Oil Pump Examination The accessory case was removed, revealing the engine oil pump. The pump housing exhibited a crack branching from the upper mounting hole through to the support web at the oil pump input drive, then beyond the web and down to the pumpbase. Removal of the pump revealed that one tooth from the left-hand impeller gear had fractured and was missing; the right gear retained all of its teeth, but had fractured at the root between two of the teeth, splaying open the gear such that it no longer positively attached to the oil pump input drive shaft. Both gears were of the steel type. The pump housing exhibited mushroom-like deformation at the interface with the input drive. The oil pump was sent to the NTSB Materials Laboratory for metallurgical examination. Analysis revealed that the fracture surfaces for both gears exhibited dull, tortuous features consistent with overstress failure. No indications of other failure modes, such as fatigue or corrosion were found on the gear fracture surfaces. The inner surface of the pump housing exhibited smearing and witness marks consistent with gear tooth contact, and the crack from the pump base to the input drive shaft web displayed a witness mark along its entire length consistent with gear tooth contact. Maintenance Records According to maintenance logbooks, the engine was overhauled in 2004, at which time it had accumulated a total of 7,061 flight hours, at a tachometer time of 7,866 hours. The most recent annual inspection was performed on April 1, 2013, at a tachometer time of 10,160 hours. ## Aircraft - Registration: [N20800](https://openairdocs.org/deregistered/N20800-2014-12-18), registration cancelled 2014-12-18, S/N 17263840, built 1975 (OpenAirDocs) - Reported make and model: CESSNA 172M - Registry model: [Cessna 172M](https://openairdocs.org/model/cessna-172m) (registry code 2072418) (OpenAirDocs) - Registry engine: [Lycoming O-320-E2D](https://openairdocs.org/engine/lycoming-o-320-e2d) (registry code 42123, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: 17263840 - Year built: 1975 - Airframe hours: 10160 - Engines: LYCOMING O-320-E2D 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 1, 2013, 15 hours before - Departed: 1O2, Lakeport, CA - Destination: 1O2, Lakeport, CA - Airport: 1O2, Lakeport, runway 10, 3,600 × 60 ft, asphalt - Equipment: Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review March 5, 2012; seat: left; restraint: 3-point; flight hours: 513 total, 200 in this make and model, 442 as pilot in command, 8.5 in the last 90 days, 2.2 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 27 °F - Altimeter: 29.95 inHg - Observed at: UKI, 16 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 20130429007989A](https://openairdocs.org/incident/20130429007989A), Apr 29, 2013: Cessna 172M, Kelseyville, CA, Substantial damage. Aircraft took off from Lampson field, on climb out, engine began running roughly, RPM dropped, pilot turned aircraft back for Lampson, then engine stopped.… ## Docket (12 files) The files NTSB released with the investigation on September 9, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=86857. 17.8 MB in all. - Pilot-Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 818 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416255&FileExtension=.PDF&FileName=Pilot-Operator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Materials Lab Factual Report (item 2, .PDF, 2.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416256&FileExtension=.PDF&FileName=Materials%20Lab%20Factual%20Report-Master.PDF - Photo 1 - Damage to Right Wing (item 3, .PDF, 371 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416258&FileExtension=.PDF&FileName=Photo%201%20-%20Damage%20to%20Right%20Wing-Master.PDF - Photo 2 - Oil Screen (item 4, .PDF, 2.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416259&FileExtension=.PDF&FileName=Photo%202%20-%20Oil%20Screen-Master.PDF - Photo 3 - Oil Filter Element (item 5, .PDF, 3.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416260&FileExtension=.PDF&FileName=Photo%203%20-%20Oil%20Filter%20Element-Master.PDF - Photo 4 - Number 2 Cylinder (item 6, .PDF, 2.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416261&FileExtension=.PDF&FileName=Photo%204%20-%20Number%202%20Cylinder-Master.PDF - Photo 5 - Crankshaft (item 7, .PDF, 2.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416262&FileExtension=.PDF&FileName=Photo%205%20-%20Crankshaft-Master.PDF - Photo 6 - Accessory Case and Oil Pump (item 8, .PDF, 2.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416263&FileExtension=.PDF&FileName=Photo%206%20-%20Accessory%20Case%20and%20Oil%20Pump-Master.PDF - Record of Conversation, FAA Inspector (item 9, .PDF, 87 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416264&FileExtension=.PDF&FileName=Record%20of%20Conversation,%20FAA%20Inspector-Master.PDF - Maintenance Logbook Excerpts (item 10, .PDF, 373 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416265&FileExtension=.PDF&FileName=Maintenance%20Logbook%20Excerpts-Redacted.PDF - Release of Wreckage, NTSB Form 6120.15 (item 11, .PDF, 131 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416266&FileExtension=.PDF&FileName=Release%20of%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF - Updated Release of Aircraft Wreckage, NTSB Form 6120.15 (item 12, .PDF, 1.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417927&FileExtension=.PDF&FileName=Updated%20Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.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.