# NTSB LAX99LA159: Cessna R182, N7317X, San Luis Obispo, CA, April 21, 1999 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 20, 1999, 18:34 local (Apr 21, 1999, 01:34 UTC) - Place: San Luis Obispo, CA - Coordinates: 35.290298, -120.809814 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.2903&lon=-120.8098&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report June 23, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 46143 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX99LA159 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/46143/pdf - Page: https://openairdocs.org/ntsb/LAX99LA159 ## Probable cause The inadequate preflight inspection of the aircraft by the pilot-in-command which resulted in a loss of engine power due to water contamination in the fuel system. A factor in the accident was an improper maintenance alteration which disabled a fuel sump drain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - nonmechanical, descent - normal - fuel system - contamination,water (cause) - fuel system,drain - disabled - maintenance - improper, unknown (contributing factor) - aircraft preflight - inadequate, pilot in command (cause) - Forced landing, descent - emergency - On ground/water collision with object, landing - roll - object - sign ## Analysis The pilot reported that he was about 6 miles northwest of the airport, returning to the airport for landing, the engine abruptly and completely ceased delivering power. The aircraft descended through a stratus cloud layer and broke out beneath a 900-foot ceiling. The pilot determined that the aircraft would not glide to the airport and made an emergency landing in an open field beside a highway. The right wing struck a sign during the landing. FAA inspectors reported that the engine fuel sump contained a clear fluid resembling water, and that the right-hand fuel tank sump drain had a threaded plug installed which precluded routine sampling of the tank for water. ## Factual narrative On April 20, 1999, at 1834 hours Pacific daylight time, a Cessna R182, N7317X, was substantially damaged when the right wing collided with a sign during an off-airport emergency landing following loss of engine power near San Luis Obispo, California. The commercial pilot was not injured. Visual meteorological conditions prevailed and no flight plan was filed. The personal flight, operated by the owner under 14 CFR Part 91, departed from San Luis Obispo at 1800. The pilot reported that he was returning for landing when the engine stopped abruptly about 6 miles northwest of the airport. The aircraft descended through a stratus cloud layer and broke out beneath a 900-foot ceiling. The pilot determined that the aircraft would not glide to the airport and made an emergency landing in an open field alongside a highway. In his report to the Safety Board, the pilot reported there were no mechanical malfunctions with the aircraft, and that water was found in the carburetor at the emergency landing site. He reported that he drained both fuel tank sumps (left and right), as well as the firewall gascolator as part of his preflight inspection. Inspectors from the San Jose Flight Standards District Office reported that the engine fuel sump contained a clear fluid resembling water, and that the right-hand fuel tank sump drain had a threaded plug installed which precluded routine sampling of the tank for water. ## Aircraft - Registration: [N7317X](https://openairdocs.org/aircraft/N7317X), registered now, S/N R18200073 (OpenAirDocs) - Reported make and model: Cessna R182 - Registry model: [Cessna R182](https://openairdocs.org/model/cessna-r182) (registry code 2072734) (OpenAirDocs) - Registry engine: [Lycoming 0-540 series](https://openairdocs.org/engine/lycoming-0-540-series) (registry code 41532, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: R18200073 - Airframe hours: 1607 - Engines: Lycoming O-540-J3C5D 235 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Lynn D. Mahin - Airworthiness certificate: Standard, Normal - Last inspection: Annual, February 3, 1998, 12 hours before - Departed: SBP, CA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 77; flight instructor, commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 2,429 total, 508 in this make and model, 2,360 as pilot in command, 2 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Dusk - Wind: 310° at 19 knots, gusting 27 - Visibility: 15 statute miles - Lowest ceiling: 20,000 ft broken - Temperature: 55 °F, dew point 48 °F - Altimeter: 29.00 inHg - Observed at: SBP, 6 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 19990420019579A](https://openairdocs.org/incident/19990420019579A), Apr 20, 1999: Cessna R182, San Luis Obispo, CA, Substantial damage. On April 20, 1999, at 1834 hours pacific daylight time, a Cessna R182, N7317X, was substantially damaged when the right wing collided with a sign during an off… ## Other investigations on N7317X (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 LAX02LA050](https://openairdocs.org/ntsb/LAX02LA050), Dec 17, 2001: Cessna R182 (N7317X), Santa Maria, CA, substantial damage. Probable cause: Inadequate maintenance and inspection of the engine dual magneto that resulted in a loss of engine power during a critical phase of flight, and the subsequent undershoot forced landing in soft… 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.