# NTSB SEA08CA010: Welch RV-9, N475TW, Bigfork, MT, October 14, 2007 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: October 14, 2007, 14:30 local (20:30 UTC) - Place: Bigfork, MT - Coordinates: 48.080554, -114.001663 - Nearby events: https://openairdocs.org/map.md?lat=48.0806&lon=-114.0017&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report December 20, 2007 - Report: Approved by Office Director - NTSB case key (mKey): 66898 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA08CA010 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/66898/pdf - Page: https://openairdocs.org/ntsb/SEA08CA010 ## Probable cause Fuel starvation while on downwind for landing. The pilot's inadequate in-flight fuel management planning was a factor. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - nonmechanical, approach - vfr pattern - downwind - in-flight planning/decision - inadequate, pilot in command (contributing factor) - fluid,fuel - starvation (cause) - Forced landing, descent - emergency - In flight collision with terrain/water, approach - vfr pattern - final approach - terrain condition - roadway/highway ## Analysis The pilot reported that at the completion of a third flight for the day, he was returning to the airport for landing. The flight entered downwind when the engine sputtered, ran smoothly, then lost power. The pilot switched the fuel selector from the right tank to the left tank and attempted to restart the engine. The engine would not start and the pilot initially thought that he could make the end of the runway, however the aircraft lost altitude and the landing gear hit the edge of the road short of the runway and the aircraft slid through a barb wire fence and onto the runway. Both wings and the tail section were substantially damaged. After the accident, the pilot stated that he found the right fuel tank "extremely low" and the left fuel tank about a third full. The pilot continued to state that after changing to the left fuel tank, he believed that the fuel pump did not fill the header tank fast enough for an engine restart. ## Factual narrative The pilot reported that at the completion of a third flight for the day, he was returning to the airport for landing. The flight entered downwind when the engine sputtered, ran smoothly, then lost power. The pilot switched the fuel selector from the right tank to the left tank and attempted to restart the engine. The engine would not start and the pilot initially thought that he could make the end of the runway, however the aircraft lost altitude and the landing gear hit the edge of the road short of the runway and the aircraft slid through a barb wire fence and onto the runway. Both wings and the tail section were substantially damaged. After the accident, the pilot stated that he found the right fuel tank "extremely low" and the left fuel tank about a third full. The pilot continued to state that after changing to the left fuel tank, he believed that the fuel pump did not fill the header tank fast enough for an engine restart. ## Aircraft - Registration: [N475TW](https://openairdocs.org/deregistered/N475TW-2014-10-27), registration cancelled 2014-10-27, S/N 90475, built 2001 (OpenAirDocs) - Reported make and model: Welch RV-9 - Registry model: [Welch Thomas RV9](https://openairdocs.org/model/welch-thomas-rv9) (registry code 05617WD) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 90475 - Engines: Subaru Unknown reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Bruce W. Piasecki - Registered owner: Thomas Welch - Airworthiness certificate: Special, Experimental (Special) - Departed: 53U, Bigfork, MT - Destination: 53U - Airport: 53U, Ferndale, runway 33, 3,500 × 95 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 56; private; airplane ratings: single-engine land; medical: class 3; flight hours: 354 total, 72 in this make and model, 20 in the last 90 days, 12 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none ## 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 20071014021929A](https://openairdocs.org/incident/20071014021929A), Oct 14, 2007: Amtr RV9, Big Fork, MT, Substantial damage. (-23) On 14 October 2007, at 1430 MDT, a homebuilt RV-9, N475TW, registered to [privacy data omitted], collided with a fence post when the aircraft landed… ## Other investigations on N475TW (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 CEN11CA065](https://openairdocs.org/ntsb/CEN11CA065), Nov 3, 2010: Welch Thomas RV9 (N475TW), Sac City, IA, substantial damage. Probable cause: The pilot's loss of directional control while landing with a gusting wind. 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.