# NTSB WPR12LA283: Stinson 108, N773C, Stanley, ID, June 30, 2012 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: June 30, 2012, 14:15 local (20:15 UTC) - Place: Stanley, ID - Coordinates: 44.406665, -115.351669 - Nearby events: https://openairdocs.org/map.md?lat=44.4067&lon=-115.3517&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Loss of lift](https://openairdocs.org/ntsb-events/500) - Highest injury: Serious injuries - Injuries: 1 serious, 3 minor - Status: Completed, report September 5, 2013 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 84136 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR12LA283 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/84136/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=84136 - Page: https://openairdocs.org/ntsb/WPR12LA283 ## Probable cause The pilot’s inadequate preflight planning and decision to takeoff at a density altitude outside of the airplane’s takeoff performance envelope, with a tailwind, and near the airplane’s maximum gross weight, which resulted in the airplane’s inability to climb and clear trees. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Stinson 108-3, 4 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=9230408), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Aircraft capability: climb capability](https://openairdocs.org/ntsb-findings/01061010): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause); cases with it: [Stinson 108-3, 1 case](https://openairdocs.org/ntsb-findings/01061010/cases.md?model=9230408), [All aircraft, 183 cases](https://openairdocs.org/ntsb-findings/01061010/cases.md) - [Temp/humidity/pressure: high density altitude](https://openairdocs.org/ntsb-findings/03031020): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Stinson 108-3, 2 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md?model=9230408), [All aircraft, 278 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md) - [Wind: tailwind](https://openairdocs.org/ntsb-findings/03034015): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Stinson 108-3, 3 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md?model=9230408), [All aircraft, 594 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md) - [Wind: gusts](https://openairdocs.org/ntsb-findings/03034045): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Stinson 108-3, 5 cases](https://openairdocs.org/ntsb-findings/03034045/cases.md?model=9230408), [All aircraft, 1,199 cases](https://openairdocs.org/ntsb-findings/03034045/cases.md) - [Object/animal/substance: tree(s)](https://openairdocs.org/ntsb-findings/03022020): Environmental issues › Physical environment · Not specified; cases with it: [Stinson 108-3, 3 cases](https://openairdocs.org/ntsb-findings/03022020/cases.md?model=9230408), [All aircraft, 933 cases](https://openairdocs.org/ntsb-findings/03022020/cases.md) - [Planning/preparation: performance calculations](https://openairdocs.org/ntsb-findings/02061010): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Stinson 108-3, 1 case](https://openairdocs.org/ntsb-findings/02061010/cases.md?model=9230408), [All aircraft, 114 cases](https://openairdocs.org/ntsb-findings/02061010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Prior to flight: Preflight or dispatch event](https://openairdocs.org/ntsb-events/030); cases with it: [Stinson 108-3, 1 case](https://openairdocs.org/ntsb-events/030/sequence.md?model=9230408), [All aircraft, 355 cases](https://openairdocs.org/ntsb-events/030/sequence.md) - [Takeoff: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Stinson 108-3, 2 cases](https://openairdocs.org/ntsb-events/400/sequence.md?model=9230408), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) - [Takeoff: Loss of lift](https://openairdocs.org/ntsb-events/500) (defining event); cases with it: [Stinson 108-3, 2 cases](https://openairdocs.org/ntsb-events/500/sequence.md?model=9230408), [All aircraft, 252 cases](https://openairdocs.org/ntsb-events/500/sequence.md) - [Takeoff: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Stinson 108-3, 15 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=9230408), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis Before taking off from the 5,000-foot turf-dirt airstrip located at an altitude of 6,370 feet mean sea level, the pilot checked his performance charts and calculated that the density altitude was about 9,200 feet; this was 3,200 feet above the 6,000-foot maximum altitude listed in the takeoff performance charts. He also noted that at the time of departure, the wind was from 30 degrees at 10 knots, with gusts to 20 knots, which was close to a nearly direct tailwind for the takeoff from runway 23. The pilot indicated that the airplane was within 86 pounds of its maximum gross takeoff weight. When the airplane was about three-quarters of the way down the runway during the takeoff roll and not yet airborne, the pilot was about to abort the takeoff, but a gust of wind lifted the airplane in the air. The pilot thought the airplane would remain airborne, but when he could not get the airplane to climb as expected, he attempted to locate an open field to land in. However, the airplane subsequently encountered a downdraft, collided with a stand of trees, and came to rest inverted about 1.64 nautical miles from the departure end of the runway. A postaccident examination of the airplane and engine revealed no mechanical malfunctions or failures that would have precluded normal operation. ## Factual narrative On June 30, 2012, about 1415 mountain daylight time, a Stinson 108-3, N773C, was substantially damaged after impacting terrain during initial climb near the Bruce Meadows Airport (U63), Stanley, Idaho. The certified commercial pilot sustained serious injuries, and the three passengers sustained minor injuries. Visual meteorological conditions prevailed for the local flight, which was being operated in accordance with 14 Code of Federal Regulations Part 91, and a flight plan was not filed. The flight was destined for the McCall Municipal Airport (MYL), McCall, Idaho. The pilot reported a departure time of 1400. In a report submitted to the National Transportation Safety Board investigator-in-charge (IIC), as well as during a personal telephone conversation with the IIC about 5 weeks after the accident, the pilot reported that prior to departure he checked the airplane’s performance charts and determined that the density altitude to be about 9,200 feet; this was determined to be 3,200 feet above the maximum altitude listed in the takeoff performance charts for this make and model airplane equipped with a metal propeller, or 6,000 feet. The pilot further reported that while on takeoff roll from the near mile long turf-dirt [air]strip, he was not getting as much lift as expected. The pilot added that when he was about three-quarters of the way down the [5,000-foot] runway, elevation 6,370 feet mean sea level (msl) [and still not airborne], he was going to abort the takeoff but a gust of wind put the airplane in the air. The pilot stated that he thought he would be ok, but when he could not get the airplane to climb as expected he attempted to locate an open field to land in, but got caught in a downdraft and subsequently impacted a stand of trees. The airplane came to rest inverted about 1.64 nautical miles (nm) from the departure end of runway 23, at an elevation of 6,432 feet msl. The pilot reported to the IIC that at the time of takeoff the airplane weighed 2,314 pounds; the airplane’s maximum gross takeoff weight is 2,400 pounds. The pilot reported no anomalies with the airplane or the engine prior to or during the flight that would have precluded normal operation. A Federal Aviation Administration (FAA) aviation safety inspector reported that the airplane had sustained substantial damage to the main fuselage, the empennage, and both wings. The inspector further reported that an inspection of the mixture control was performed but the control cable was bent preventing the movement at the carburetor. The cable was disconnected at the carburetor mixture control arm and the arm moved freely from stop to stop. The inspector also provided the IIC with documentation relative to the airplane’s Franklin, model 6A4-165-B3 engine, which was equipped with a Marvel Schebler, model MA-4-5 carburetor. With respect to USE OF MIXTURE CONTROL IN FLIGHT, the information revealed, “When adjusting the mixture control for altitudes higher than 3,000 feet, move the[mixture] control in and out slowly, with the throttle at cruising position until the highest RPM is attained. The carburetor mixture will then be correctly adjusted for that throttle position and load at that particular altitude.” When questioned by the IIC what the leaning procedures were for the engine, the pilot stated that the Franklin engine could not be leaned for takeoff. The inspector’s onsite and postaccident examinations of the airplane and engine revealed no mechanical anomalies that would have prevented normal operation. Local law enforcement personnel provided the IIC with statements submitted by both backseat passengers. The left rear seat passenger reported that after takeoff and when they were above the trees, it felt like they encountered a pocket of air that pushed them down into the trees. The right rear seat passenger stated that about 5 minutes into the flight they didn’t have enough lift or air [to fly], which is when the pilot called to brace for impact. The passenger reported that the airplane then flew into the trees, was twisting, and then hit the ground and nosed over. Law enforcement personnel reported to the IIC that the left rear seat passenger stated that the right front seat passenger did not remember the crash at all, nor did he remember a lot of the day. At 1351, the weather reporting facility at the McCall Municipal Airport (MYL), McCall, Idaho, the closest weather reporting facility in proximity to the accident site, which is located about 44 nautical nm northwest, reported wind 160 degrees at 8 knots, variable from 120 degrees to 190 degrees, visibility 10 miles, sky clear, temperature 27 degrees Celsius (C), dew point 3 degrees C, and an altimeter setting of 30.00 inches of mercury. ## Aircraft - Registration: [N773C](https://openairdocs.org/deregistered/N773C-2018-01-09), registration cancelled 2018-01-09, S/N 108-3773, built 1947 (OpenAirDocs) - Reported make and model: STINSON 108 (3) - Registry model: [Stinson 108-3](https://openairdocs.org/model/stinson-108-3) (registry code 9230408) (OpenAirDocs) - Registry engine: [Franklin 6A4165 series](https://openairdocs.org/engine/franklin-6a4165-series) (registry code 27025, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 108-3773 - Airframe hours: 1544 - Engines: Franklin 6A4165 165 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Leslie B Gropp - Registered owner: Leslie B Gropp - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 17, 2010, 34 hours before - Departed: U63, Stanley, ID - Destination: MYL, McCall, ID - Airport: U63, Bruce Meadows Airport, runway 23, 5,000 × 110 ft, grass/turf ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 70; injuries: serious; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: helicopter; medical: class 3, with waivers/limitations; last flight review April 26, 2011; seat: left; flight hours: 4,927 total, 124 in this make and model, 2,580 as pilot in command, 11 in the last 90 days, 6 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 160° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 81 °F, dew point 37 °F - Altimeter: 30.00 inHg - Observed at: MYL, 44 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 20120630013409A](https://openairdocs.org/incident/20120630013409A), Jun 30, 2012: Stinson 108-3, Stanley, ID, Substantial damage. On 30 June 2012 at approximately 1400 N773C, a stnson 108-3PILOTED by [privacy data omitted] and three passengers, departed from Bruce Meadows (U63) no runway… ## Docket (9 files) The files NTSB released with the investigation on June 27, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=84136. 6.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395556&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - FAA Inspector's Report (Carburetor Control) (item 2, .PDF, 47 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395558&FileExtension=.PDF&FileName=FAA%20Inspector%27s%20Report%20(Carburetor%20Control)-Redacted.PDF - Carburetor Operational Data (item 3, .PDF, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395557&FileExtension=.PDF&FileName=Carburetor%20Operational%20Data-Master.PDF - Takeoff Performance Data (item 4, .PDF, 252 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395559&FileExtension=.PDF&FileName=Takeoff%20Performance%20Data-Master.PDF - Record of Conversation (Pilot-in-Command) (item 5, .PDF, 109 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395561&FileExtension=.PDF&FileName=Record%20of%20Conversation%20(Pilot-in-Command)-Master.PDF - Photo 1 - overhead view of accident site area (item 6, .PDF, 536 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395564&FileExtension=.PDF&FileName=Photo%201%20-%20overhead%20view%20of%20accident%20site%20area-Master.PDF - Photo 2 - view #1 of accident site (item 7, .PDF, 122 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395565&FileExtension=.PDF&FileName=Photo%202%20-%20view%20%231%20of%20accident%20site-Master.PDF - Photo 3 - view #2 of accident site (item 8, .PDF, 123 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395566&FileExtension=.PDF&FileName=Photo%203%20-%20view%20%232%20of%20accident%20site-Master.PDF - Photo 4 - view #3 of accident site (item 9, .PDF, 123 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395567&FileExtension=.PDF&FileName=Photo%204%20-%20view%20%233%20of%20accident%20site-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.