# NTSB CEN14LA417: Stinson 108 1, N9034K, Bruno, MN, July 18, 2014 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 18, 2014, 15:41 local (20:41 UTC) - Place: Bruno, MN - Coordinates: 46.280654, -92.659355 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=46.2807&lon=-92.6594&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report September 1, 2016 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA FSDO - NTSB case key (mKey): 89846 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN14LA417 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/89846/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=89846 - Page: https://openairdocs.org/ntsb/CEN14LA417 ## Probable cause The total loss of engine power due to an anomaly with the carburetor system that could not be determined during postaccident examination. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine fuel and control: fuel control/carburetor](https://openairdocs.org/ntsb-findings/01057322): Aircraft › Aircraft power plant · Malfunction (probable cause); cases with it: [Stinson 108-1, 1 case](https://openairdocs.org/ntsb-findings/01057322/cases.md?model=9230404), [All aircraft, 195 cases](https://openairdocs.org/ntsb-findings/01057322/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Stinson 108-1, 4 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=9230404), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) ## Analysis According to the private pilot, after about 30 minutes of uneventful cross-country flight in the float-equipped airplane and about 2,000 ft above ground level, the engine sputtered for about 10 seconds and then lost all power. The pilot initiated emergency procedures for a restart and located an off-airport landing site while in an emergency descent. The airplane touched down on its floats in a grassy field. Examination of the airplane revealed structural damage to the fuselage adjacent to the float attachment points. No obvious anomalies were found with the engine or fuel system on scene. After the airplane wreckage was recovered, maintenance personnel were able to start and run the engine with an external fuel supply. The engine started and ran for about 30 seconds and then stopped. After the run attempt, the fuel gascolator and carburetor intake screen were removed and cleaned. No significant debris was found. After examining the remainder of the engine, the engine was started again, ran for about 1 minute, and stopped again. A replacement carburetor was then installed. The engine was started and ran normally with the replacement carburetor. ## Factual narrative On July 18, 2014, about 1541 central standard time, a Stinson 108-1 single engine float equipped airplane, N9034K, registered to Mimus Aero LLC, Minneapolis, Minnesota, and operated by a private individual, was substantially damaged during a forced landing after a loss of engine power near Bruno, Minnesota. The private pilot was not injured. The personal cross country flight was being conducted under the provisions of Federal Code of Regulations Part 91. A flight plan was not filed and visual meteorological condition prevailed throughout the area. The flight originated from the Sky Harbor Airport (DYT), Duluth, Minnesota, about 1510, and was enroute to the Surfside Seaplane Base (BY4), Lino Lakes, Minnesota, when the accident occurred. According to the pilot, about 30 minutes after departing DYT, at an altitude on 2,000 AGL, the engine sputtered for about 10 seconds and then lost all power. The pilot initiated emergency procedures for a restart and located an off airport landing site while in an emergency descent. The airplane touched down on its floats in a grassy field and sustained substantial damage to the fuselage. The pilot exited the airplane with no injuries. FAA inspection of the airplane on scene revealed bucking damage of the fuselage just aft of the right cabin door and additional fuselage buckling near the left aft attachment point of the floats. Both float attachment struts were found broken. There was marks found on the aft face of the propeller blades consistent with contact of the walk wire between the floats. The airplane was found resting in a slight right wing low attitude and fuel flowed freely from the engine fuel sump. Fuel was drained from both tanks and the fuel strainer (7 gallons in the left tank and 21 gallons in the right tank). All of the fuel appeared to be clean, not contaminated, and had the appearance of 100LL aviation fuel. The fuel selector valve was in the right tank position and appeared to operate properly within its detents. The top spark plugs were removed and the engine rotated by hand with the propeller in the normal rotation direction. All 6 cylinders appeared to have good compression. Both magneto impulse couplings appeared to snap normally while rotating the engine. All of the spark plugs appeared to be in good condition. The airplane was found resting in a slight right wing low attitude and fuel flowed freely from the engine fuel sump. No obvious anomalies were found with the engine on scene. After the airplane wreckage was recovered, maintenance personnel were able to start and run the engine with an external fual supply. The engine started and ran for about 30 seconds and then stopped. After the run attempt, the fuel gascolator and carburetor intake screen were removed and cleaned. No significant debris was found. A small amount of debris was found in the carburetor fuel bowl. After inspecting the remainder of the engine, the engine was started again, ran for about 1 minute, and stopped again. Areplacement carburetor was then installed. The engine was started and ran normally with the replacement carburetor. ## Aircraft - Registration: [N9034K](https://openairdocs.org/aircraft/N9034K), registered now, S/N 108-2034, built 1947 (OpenAirDocs) - Reported make and model: STINSON 108 1 (UNDESIGNAT) - Registry model: [Stinson 108-1](https://openairdocs.org/model/stinson-108-1) (registry code 9230404) (OpenAirDocs) - Registry engine: [Franklin 6A4150 series](https://openairdocs.org/engine/franklin-6a4150-series) (registry code 27024, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 108-2034 - Year built: 1947 - Airframe hours: 2130 - Engines: Continental O-470 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, August 29, 2013 - Departed: DYT, Duluth, MN - Destination: 8Y4, Lino Lakes, MN - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; injuries: none; private; airplane ratings: single-engine land; medical: class 2, without waivers/limitations; last flight review November 17, 2012; seat: left; flight hours: 279 total, 160 in this make and model, 12 in the last 90 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 190° at 14 knots, gusting 18 - Visibility: 10 statute miles - Lowest ceiling: 9,000 ft broken - Temperature: 79 °F, dew point 61 °F - Altimeter: 29.96 inHg - Observed at: ANE, 4 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 20140718012369A](https://openairdocs.org/incident/20140718012369A), Jul 18, 2014: Stinson 108-1, Bruno, MN, Substantial damage. Pilot reported that approximately 1/2 hour into a flight from kdyt to 8Y4 while at an altitude of approximately 2000' AGL, the engine sputtered for… ## Docket (3 files) The files NTSB released with the investigation on August 4, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=89846. 981 KB in all. - Memorandum for the Record FAA On-Scene Observations (item 1, .PDF, 241 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40442869&FileExtension=.PDF&FileName=Memorandum%20for%20the%20Record%20FAA%20On-Scene%20Observations-Master.PDF - Memorandum for the Record Engine Inspection Summary (item 2, .PDF, 160 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40442870&FileExtension=.PDF&FileName=Memorandum%20for%20the%20Record%20Engine%20Inspection%20Summary-Master.PDF - Weather Information (item 3, .PDF, 580 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40442871&FileExtension=.PDF&FileName=Weather%20Information-Master.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.