# NTSB LAX97LA018: Cessna 172P, N6187K, Kingsburg, CA, October 15, 1996 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: October 15, 1996, 10:05 local (17:05 UTC) - Place: Kingsburg, CA - Coordinates: 36.48088, -119.500083 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.4809&lon=-119.5001&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report September 30, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 29665 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX97LA018 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/29665/pdf - Page: https://openairdocs.org/ntsb/LAX97LA018 ## Probable cause the student pilot's use of an excessively lean mixture, which led to engine overheating, detonation, subsequent failure of the number 2 piston, and a forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, cruise - normal - mixture - improper use of, pilot in command (cause) - engine assembly - overtemperature (cause) - misc,engine pre-ignition and/or detonation (cause) - engine assembly,piston - failure (cause) - engine assembly,connecting rod - disconnected - Forced landing, emergency descent/landing - On ground/water collision with object, emergency landing - object - building(nonresidential) - object - tree(s) ## Analysis As a student pilot was en route on his third supervised solo cross-country flight, the engine suddenly began running rough. Oil was observed to cover most of the front windscreen. Subsequently, the engine lost power, the student made a forced landing in a clearing, and the airplane collided with a tree and a building. An FAA inspector performed an examination of the wreckage, and observed a 2-inch diameter hole in the engine's upper case in the vicinity of the number 2 cylinder. A further examination revealed that the connecting rod to the number 2 piston was disconnected from the piston due to a failure of the piston skirt in the piston pin area. The rings on all pistons appeared to have been sticking, with over temperature signatures noted on all the intake and exhaust valves. The tops of the piston were abnormally clean. The engine had a total time of 3,794.5 hours since new and 1,987.0 hours since the last major overhaul. ## Factual narrative On October 15, 1996, at 1005 hours Pacific daylight time, a Cessna 172P, N6187K, operated by the Sierra Academy, Inc., Livermore, California, made a forced landing in a field near Kingsburg, California. The airplane was destroyed during landing rollout upon colliding with a tree and a building. The student pilot received minor injuries. Visual meteorological conditions prevailed, and a visual flight rules flight plan was filed for the student's third solo instructional cross-country flight. The flight originated from Livermore about 0900. The Federal Aviation Administration (FAA) reported that while the pilot was cruising at 5,500 feet mean sea level the engine suddenly began running rough and oil was observed covering most of the front windscreen. Engine power was subsequently lost and the pilot made a forced landing. The FAA performed an examination of the wreckage and observed a 2-inch diameter hole in the engine's upper case in the vicinity of the number 2 cylinder. A further examination revealed that the connecting rod to the number 2 piston was disconnected from the piston due to the failure of the piston skirt in the piston pin area. The rings in all pistons appeared to have been sticking, with over temperature signatures noted on all the intake and exhaust valves. The tops of each piston were abnormally clean. The engine was installed in the airframe on June 9, 1993. By the accident date, it had a total time of 3,794.5 hours, and 1,987.0 hours since last major overhaul. ## Aircraft - Registration: [N6187K](https://openairdocs.org/deregistered/N6187K-2002-08-05), registration cancelled 2002-08-05, S/N 17274172, built 1980 (OpenAirDocs) - Reported make and model: Cessna 172P - Registry model: [Cessna 172P](https://openairdocs.org/model/cessna-172p) (registry code 2072436) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 17274172 - Airframe hours: 4107 - Engines: Lycoming O-320-D2J 160 horsepower reciprocating - Damage: Destroyed - Flight: Instructional, Part 91 - Operator: Sierra Academy, Inc. - Registered owner: Christiansen Aviation, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, September 26, 1996, 40 hours before - Departed: LVK, LIVERMORE, CA - Destination: PTV, PORTERVILLE, CA - Flight plan: VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 24; student; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 70 total, 70 in this make and model, 10 as pilot in command, 70 in the last 90 days, 25 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 70 °F - Altimeter: 30.00 inHg ## 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 19961015032379A](https://openairdocs.org/incident/19961015032379A), Oct 15, 1996: Cessna 172P, Kingsburg, CA, Destroyed. At cruise rough engine oil on shield lost power. Hit tree and building landing. Piston skirt failed. Thru a rod. 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.