# NTSB DEN99LA008: Stinson 108-3, N569C, Jackson Hole, WY, October 13, 1998 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: October 13, 1998, 11:20 local (17:20 UTC) - Place: Jackson Hole, WY - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor, 1 uninjured - Status: Completed, report March 31, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 45111 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN99LA008 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/45111/pdf - Page: https://openairdocs.org/ntsb/DEN99LA008 ## Probable cause The pilot's inability to maintain adequate airspeed which resulted in an inadvertent stall/mush. Factors contributing to the accident were the unfavorable weather condition, mountain wave and the high density altitude. ## Analysis As the pilot taxied out for takeoff, he noted that the windsock indicated a no wind weather situation (he had not received a forecasted winds aloft briefing). The pilot reported that he departed east towards the mountains and was climbing at 85 to 90 knots indicated airspeed (IAS). He turned the airplane southwest and climbed through 10,000 feet (approximately 11,000 feet density altitude) when his IAS dropped between 60 to 65 knots. He said the airplane began to descend at 800 to 1,200 feet per minute, and he could not get the airplane's nose down 'even with full forward yoke.' The pilot reported that he kept the wings level and 'pulled [the] yoke back full somewhere close to impacting the trees.' ## Factual narrative On October 13, 1998, approximately 1120 mountain daylight time, a Stinson, 108-3, N569C (NC569C), was destroyed when it collided with terrain during an en route climb from Jackson Hole Airport, Jackson Hole, Wyoming. The commercial pilot and one passenger sustained minor injuries; however, one passenger was not injured. The aircraft was owned/operated by the pilot under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the local flight which originated approximately 15 minutes before the accident. No flight plan had been filed. According to the pilot, he was taking two friends for a "short local flight." As he taxied out for takeoff, he noted that the windsock indicated a no wind weather situation (he had not received a forecasted winds aloft briefing). The pilot reported that he departed east towards the mountains and was climbing at 85 to 90 knots indicated airspeed (IAS). He turned the airplane southwest and climbed through 10,000 feet (approximately 11,000 feet density altitude) when his IAS dropped 60 to 65 knots. He said the airplane began to descend at 800 to 1,200 feet per minute, and he could not get the airplane's nose down "even with full forward yoke." The pilot reported that he kept the wings level and "pulled [the] yoke back full somewhere close to impacting the trees." Postimpact fire consumed the airplane. The occupants exited the airplane and the back seat passenger walked down the mountain approximately 6 miles for help. At approximately 1630, a U.S. Forest Service helicopter arrived at the accident scene, and extracted the pilot and the front seat passenger. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, cruise - normal - weather condition - high density altitude (contributing factor) - airspeed - not possible, pilot in command (cause) - weather condition - mountain wave (contributing factor) - stall/mush - inadvertent, pilot in command (cause) - Loss of control - in flight, descent - uncontrolled - In flight collision with terrain/water, emergency descent/landing - terrain condition - mountainous/hilly - object - tree(s) ## Aircraft - Registration: [N569C](https://openairdocs.org/deregistered/N569C-2018-01-25), registration cancelled 2018-01-25, S/N 108-3569, built 1947 (OpenAirDocs) - Reported make and model: Stinson 108-3 - Registry model: [Universal Stinson 108-3](https://openairdocs.org/model/universal-stinson-108-3) (registry code 9230418) (OpenAirDocs) - Registry engine: [Lycoming 0-435](https://openairdocs.org/engine/lycoming-0-435) (registry code 41516, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 108-3569 - Airframe hours: 2500 - Engines: Lycoming O-435-C 190 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Scott P. Smith - Airworthiness certificate: Standard, Normal - Last inspection: Annual, September 15, 1998, 25 hours before - Departed: JAC, WY ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 35; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 850 total, 400 in this make and model, 850 as pilot in command, 45 in the last 90 days, 20 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 220° at 17 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 64 °F, dew point 23 °F - Altimeter: 30.00 inHg - Observed at: JAC, 12 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 19981013028959A](https://openairdocs.org/incident/19981013028959A), Oct 13, 1998: Univar 1083, Jackson Hole, WY, Destroyed. Acft was on a flight in the mountains when it encountered downdrafts whiched the acft down into the trees.(-23)encountered down draft while mountain flying… ## Other investigations on N569C (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB ANC75DAG81](https://openairdocs.org/ntsb/ANC75DAG81), Apr 10, 1975: Stinson 108-3 (N569C), Iliamna, AK, substantial damage From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date; 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.