# NTSB SEA05LA138: Bell 47G-2A, N38926, Oroville, WA, July 5, 2005 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 4, 2005, 17:30 local (Jul 5, 2005, 00:30 UTC) - Place: Oroville, WA - Coordinates: 48.958889, -119.411941 - Nearby events: https://openairdocs.org/map.md?lat=48.9589&lon=-119.4119&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report February 28, 2006 - Report: Approved by Office Director - Parties: FAA FSDO - NTSB case key (mKey): 61867 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA05LA138 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/61867/pdf - Page: https://openairdocs.org/ntsb/SEA05LA138 ## Probable cause The failure of the throttle cable housing, which permitted the engine's RPM to decay to the idle position. Contributing factors were the trees and the lack of suitable terrain for a forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, maneuvering - aerial application - throttle/power lever,cable - failure (cause) - Forced landing, descent - uncontrolled - autorotation - attempted, pilot in command - In flight collision with object, descent - uncontrolled - object - tree(s) (contributing factor) - terrain condition - none suitable (contributing factor) ## Analysis The pilot said that he was spraying cherries when the engine suddenly stopped. He attempted an autorotation, but the main rotor impacted cherry trees. The helicopter's main bubble was shattered, and the skids and frame were bent. Postimpact examination of the aircraft, by a Federal Aviation Administration Inspector, revealed that the throttle cable's housing had broken, which permitted the engine's RPM to decay to the idle position. ## Factual narrative On July 4, 2005, at 1730 Pacific daylight time, a Bell 47G-2A helicopter, N38926, was substantially damaged during a forced landing attempt, following a loss of engine power near Oroville, Washington. The commercial pilot, the sole occupant on board, was not injured. Waitsburg Helicopter Service was operating the flight under Title 14 CFR Part 137. Visual meteorological conditions prevailed for the aerial application flight. A flight plan had not been filed. The pilot said that he was spraying cherries when the engine suddenly stopped. He attempted an auto rotation, but the main rotor impacted cherry trees. The helicopter's main bubble was shattered, and the skids and frame were bent. Postimpact examination of the aircraft, by a Federal Aviation Administration Inspector, revealed that the throttle cable's housing had broken, which permitted the engine's RPM to decay to the idle position. ## Aircraft - Registration: [N38926](https://openairdocs.org/deregistered/N38926-2012-11-14), registration cancelled 2012-11-14, S/N N.A.H.1957-1, built 1973 (OpenAirDocs) - Reported make and model: Bell 47G-2A - Registry model: [Bell 47G-2](https://openairdocs.org/model/bell-47g-2) (registry code 1181008) (OpenAirDocs) - Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: N.A.H. 1957-1 - Engines: Lycoming VO-435-A1F 265 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Waitsburg Helicopter Service - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, April 1, 2005, 50 hours before - Departed: 0S7, Oroville, WA - Destination: 0S7 ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 59; injuries: none; commercial; medical: class 2, without waivers/limitations; seat: left; flight hours: 10,000 total, 10,000 as pilot in command, 150 in the last 90 days, 50 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 190° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 90 °F, dew point 37 °F - Altimeter: 29.95 inHg - Observed at: OMK, 32 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 20050704014629A](https://openairdocs.org/incident/20050704014629A), Jul 4, 2005: Bell 47G2, Oroville, WA, Substantial damage. (-23) While involved in aerial application, suffered sudden, complete loss of power. Autorotation initiated to cherry orchard nw of area being sprayed. Main… ## Other investigations on N38926 (5) 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 SEA91LA077](https://openairdocs.org/ntsb/SEA91LA077), Mar 31, 1991: Bell BH-47G2A (N38926), Waitsburg, WA, substantial damage. Probable cause: THE IMPROPER INSTALLATION OF THE MAIN ROTOR MAST NUT AND LOCK WASHER BY MAINTENANCE PERSONNEL WHICH RESULTED IN THE SEPARATION OF THE MAIN ROTOR SYSTEM. - [NTSB FTW77FPG86](https://openairdocs.org/ntsb/FTW77FPG86), Sep 19, 1977: Bell 47G2H1 (N38926), Mountain View, AR, destroyed - [NTSB FTW76DRG70](https://openairdocs.org/ntsb/FTW76DRG70), Jul 17, 1976: Bell 47G-2 (N38926), Mcallen, TX, substantial damage - [NTSB FTW75DPG68](https://openairdocs.org/ntsb/FTW75DPG68), May 26, 1975: Bell 47G-2 (N38926), Denmark, AR, substantial damage - [NTSB MKC73AK059](https://openairdocs.org/ntsb/MKC73AK059), Apr 6, 1973: Bell 47G-2 (N38926), Owatonna, MN, substantial damage 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.