# NTSB LAX98TA278: Aerospatiale SA316B, N605RA, Porterville, CA, August 27, 1998 - Type: NTSB accident investigation - Classification: Accident · No injuries · Final report - Date: August 27, 1998, 15:45 local (22:45 UTC) - Place: Porterville, CA - Coordinates: 35.959243, -118.920936 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.9592&lon=-118.9209&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report March 30, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 43825 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX98TA278 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/43825/pdf - Page: https://openairdocs.org/ntsb/LAX98TA278 ## Probable cause The pilot's failure to maintain adequate in-flight clearance between the bucket and trees resulting in the entanglement/separation of the long line and subsequent impact with and separation of the tail rotor assembly. A factor was the trees. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Rotor failure/malfunction, maneuvering - external load cable/hook - entangled (cause) - clearance - not maintained, pilot in command (cause) - external load cable/hook - separation - rotor system,tail rotor - separation - object - tree(s) (contributing factor) - terrain condition - mountainous/hilly - Loss of control - in flight, descent - uncontrolled - In flight collision with terrain/water, descent - uncontrolled ## Analysis The helicopter had a bambi bucket on a 100-foot-long line. The bucket became entangled in some trees and the line snapped and wrapped itself around the tail rotor. The tail rotor blades and gearbox separated from the aircraft and the helicopter spun to the ground and rolled down a steep slope. The pilot did not report any mechanical malfunction with the aircraft prior to the accident. Wire marks were found on the tail rotor blades and around the output shaft. ## Factual narrative On August 27, 1998, at 1545 hours Pacific daylight time, an Aerospatiale SA316B, N605RA, operated by the U.S. Department of the Interior, sustained substantial damage after entangling a bambi bucket in a tree near Porterville, California. The airline transport pilot, the sole occupant, was not injured. The public-use aircraft operating under 14 CFR Part 91 was performing a fire mission at the time of the accident. No flight plan was filed and visual meteorological conditions prevailed. Witnesses saw the helicopter fly down the side of a ridge with the bambi bucket on a 100-foot-long line. The bucket became entangled in some trees and the line snapped and wrapped itself around the tail rotor. The tail rotor blades and gearbox separated from the aircraft and the helicopter spun to the ground and rolled down a steep slope. Witnesses reported that the terrain was mountainous, with 40 to 50 degree slopes. The pilot did not report any mechanical malfunction with the aircraft prior to the accident. A Federal Aviation Administration inspector from the Fresno, California, Flight Standards District Office traveled to the site and reported that there were wire marks on the tail rotor blades and around the output shaft of the gearbox. ## Aircraft - Registration: [N605RA](https://openairdocs.org/deregistered/N605RA-2007-05-22), registration cancelled 2007-05-22, S/N 1165, built 1964 (OpenAirDocs) - Reported make and model: Aerospatiale SA316B - Registry model: [Aerospatiale SA316B ALOUETTE III](https://openairdocs.org/model/aerospatiale-sa316b-alouette-iii) (registry code 8680515) (OpenAirDocs) - Registry engine: [Turbomeca ARTOUSTEIIIB](https://openairdocs.org/engine/turbomeca-artousteiiib) (registry code 60003, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 1165 - Airframe hours: 3305 - Engines: Turbomeca ARTOUSTEIIIB 858 horsepower turbo shaft - Damage: Substantial damage - Flight: Public aircraft, Part 91 - Operator: U.S. Dept. Of The Interior - Registered owner: Roberts Aircraft Company - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 14, 1998, 230 hours before ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; airline transport, flight engineer; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane, helicopter; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 9,900 total, 3,300 in this make and model, 8,700 as pilot in command, 95 in the last 90 days, 51 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 270° at 10 knots, gusting 15 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 95 °F, dew point 57 °F - Altimeter: 29.00 inHg ## 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 19980827022279A](https://openairdocs.org/incident/19980827022279A), Aug 27, 1998: Aerosp SA316B, Porterville, CA, Substantial damage. (.19)On August 27, 1998, at 1545 hours pacific daylight time, an aerospatiale SA316B, N605RA, operated by the U.S. Department of the interior, sustained… ## Other investigations on N605RA (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 FTW81IA103](https://openairdocs.org/ntsb/FTW81IA103), Jun 9, 1981: Aerospatial SE3160 (N605RA), Ruidoso, NM, incident, minor 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.