# NTSB FTW98LA125: Piper PA-18-105, N316T, Sheridan, WY, February 6, 1998 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: February 6, 1998, 16:30 local (23:30 UTC) - Place: Sheridan, WY - Coordinates: 44.790328, -106.949409 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.7903&lon=-106.9494&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report July 13, 1998 - Report: Approved by Office Director - NTSB case key (mKey): 20536 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW98LA125 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/20536/pdf - Page: https://openairdocs.org/ntsb/FTW98LA125 ## Probable cause the pilot's improper use of carburetor heat, which resulted in loss of engine power due to carburetor ice. Factors relating to the accident were: the carburetor icing (weather) condition, and the lack of a suitable area for an emergency landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - nonmechanical, cruise - weather condition - carburetor icing conditions (cause) - fuel system,carburetor - ice (cause) - carburetor heat - improper use of, pilot in command (cause) - Forced landing, emergency descent/landing - Nose over, emergency landing - terrain condition - none suitable (contributing factor) - terrain condition - snow covered (contributing factor) ## Analysis While in cruise, on a local area personal flight, the engine lost power. The pilot attempted to regain power by placing the mixture to rich, applying carburetor heat, and switching fuel tanks. These procedures were ineffective, and the pilot conducted a forced landing beside a road. As the aircraft slowed during landing roll, the main landing gear dug into snow, and the aircraft nosed over. An examination of the aircraft revealed no evidence that would have prevented the engine from operating. The temperature and dew point were 39 and 34 degrees, respectively. According to icing probability charts, conditions were conducive to carburetor ice. ## Factual narrative On February 6, 1998, at 1630 mountain standard time, a Piper PA-18-105, N316T, nosed over during landing roll after conducting an emergency landing due to a complete loss of engine power. The private pilot and sole occupant was not injured and the aircraft sustained substantial damage. Visual meteorological conditions prevailed for this local area personal flight operating under Title 14 CFR Part 91 and no flight plan was filed. The flight originated from Sheridan, Wyoming, at 1615. According to the pilot, he was in cruise flight at 6,100 feet above mean sea level (msl) which was approximately 2,000 feet above ground level (agl) when the engine lost all power and the propeller stopped. He said he conducted an emergency landing beside a road approximately 10 miles south of Sheridan. As the aircraft slowed during landing roll, the main landing gear dug into the snow and the aircraft nosed over causing damage to the propeller, cowling, wind screen, the top of both wings, both wing struts, and the rudder. In an interview with the IIC (Investigator in Charge), the pilot stated that following the complete loss of power, he placed the mixture in the full rich position and applied carburetor heat. He also said he changed fuel tanks by switching the fuel feed from the full left tank to the 1/3 full right tank. None of these procedures had any affect on the power loss. An examination of the aircraft by a FAA Airworthiness Inspector, provided no evidence which would have prevented the engine from operating or the propeller from wind milling. The outside air temperature at Sheridan (3,900 feet msl) at the time of the accident was 39 degrees and the dew point was 34 degrees. Assuming a standard temperature lapse rate of 3 degrees per thousand foot change in altitude, and the pilot reported cruise altitude of 6,100 feet msl, the outside air temperature would have been 33 degrees and the dew point 29 degrees. According to FAA Advisory Circular 82-44, dated June 1982, these temperatures are in the range where carburetor ice can form at both climb and cruise power. A test run of the engine was not feasible. ## Aircraft - Registration: [N316T](https://openairdocs.org/aircraft/N316T), registered now, S/N 18-2430, built 1953 (OpenAirDocs) - Reported make and model: Piper PA-18-105 - Registry model: [Piper PA-18 105](https://openairdocs.org/model/piper-pa-18-105) (registry code 7101809) (OpenAirDocs) - Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: 18-2430 - Airframe hours: 4734 - Engines: Lycoming O-290-D2 135 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: John B. Kendrick III - Airworthiness certificate: Standard, Normal; Standard, Utility - Last inspection: 100 hour, January 26, 1998, 1 hours before - Departed: SHR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 39; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: front; flight hours: 194 total, 93 in this make and model, 153 as pilot in command, 15 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 160° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 39 °F, dew point 34 °F - Altimeter: 29.00 inHg - Observed at: SHR ## 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 19980206003839A](https://openairdocs.org/incident/19980206003839A), Feb 6, 1998: Piper PA18105, Sheridan, WY, Substantial damage. Power loss due carb ice. Landed in snow covered field and subsequently nosed over. (.4)while in cruise, on a local area personal flight, the engine lost power.… 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.