# NTSB SEA05LA163: Steele Safari, N13MA, Leavenworth, WA, August 4, 2005 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 4, 2005, 07:30 local (14:30 UTC) - Place: Leavenworth, WA - Coordinates: 47.629165, -120.650558 - Nearby events: https://openairdocs.org/map.md?lat=47.6292&lon=-120.6506&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 20, 2005 - Report: Approved by Office Director - Parties: Spokane FSDO - NTSB case key (mKey): 62169 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA05LA163 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/62169/pdf - Page: https://openairdocs.org/ntsb/SEA05LA163 ## Probable cause The failure of the tail rotor drive shaft during cruise flight. Factors include soft, grassy terrain at the location where the pilot executed the autorotational landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, cruise - rotor drive system,tail rotor drive shaft - sheared (cause) - Forced landing, descent - emergency - Roll over, emergency descent/landing - terrain condition - soft (contributing factor) - terrain condition - grass (contributing factor) ## Analysis While in cruise flight about 1,000 feet above ground level (agl), the pilot heard a loud grinding sound and felt a significant vibration in the airframe of the helicopter. The aircraft then swung to the right, so the pilot elected to reduce the throttle and perform an autorotation to a nearby open field. During the attempted autorotational landing on the soft grassy terrain, the aircraft touched down, bounced back into the air, turned about 300 degrees, and then touched down a second time. During the second touchdown, the aircraft rolled over onto its left side. During the accident sequence, the main rotor blades flexed downward and came in contact with the tail boom. When the pilot inspected the helicopter at the scene, he found that all of its components, except for the tail rotor drive shaft, were there at that one location. Although he searched the local area for the tail rotor drive shaft, he was unable to locate it. The drive shaft was later found by a local resident several hundred feet from the location where the helicopter touched down. After being recovered to a hangar, the aircraft was inspected by an FAA Airworthiness Inspector, who determined that the tail rotor drive shaft had failed in cruise flight at a location near where it attaches to the main rotor transmission assembly. The reason for the failure of the shaft could not be positively determined. ## Factual narrative On August 4, 2005, approximately 0730 Pacific daylight time, an experimental Steele Safari helicopter, N13MA, rolled over during an emergency landing about six miles north of Leavenworth, Washington. The commercial pilot, who was the sole occupant, was not injured, but the aircraft, which is owned and operated by the pilot, sustained substantial damage. The 14 CFR Part 91 personal cross-country flight, which departed Cashmere Airport, Cashmere, Washington, about 15 minutes prior to the accident, was being operated in visual meteorological conditions. No flight plan had been filed. There was no report of an ELT activation. According to the pilot, while in cruise flight about 1,000 feet above ground level (agl), he heard a loud grinding sound and felt a significant vibration in the airframe of the helicopter. The aircraft then swung to the right, so the pilot elected to reduce the throttle and perform an autorotation to a nearby open field. During the attempted autorotational landing on the soft grassy terrain, the aircraft touched down, bounced back into the air, turned about 300 degrees, and then touched down a second time. During the second touchdown, the skids dug into the soft terrain, and aircraft rolled over onto its left side. During the accident sequence, the main rotor blades flexed downward and came in contact with the tail boom. When the pilot inspected the helicopter at the scene, he found that all of its components, except for the tail rotor drive shaft, were there at that one location. Although he searched the local area for the tail rotor drive shaft, he was unable to locate it. The drive shaft was later found by a local resident several hundred feet from the location where the helicopter touched down. After being recovered to a hangar in Everett, Washington, the aircraft was inspected by an FAA Airworthiness Inspector from the Seattle, Washington, Flight Standards District Office. It was his determination that the tail rotor drive shaft had failed in cruise flight at a location near where it attaches to the main rotor transmission assembly. The reason for the failure of the shaft could not be positively determined. ## Aircraft - Registration: [N13MA](https://openairdocs.org/deregistered/N13MA-2005-09-15), registration cancelled 2005-09-15, S/N BB2058, built 2000 (OpenAirDocs) - Reported make and model: Steele Safari - Registry model: [Steele David L SAFARI HELICOPTER](https://openairdocs.org/model/steele-david-l-safari-helicopter) (registry code 05610IQ) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Helicopter, amateur-built - Serial number: BB2058 - Airframe hours: 308 - Engines: Lycoming O-320-B2C 160 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Kurt Mason - Registered owner: Kurt Mason and David Steele - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, February 1, 2005, 92 hours before - Departed: 8S2, Cashmere, WA - Destination: KPAE, Everett, WA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 71; injuries: none; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 3; last flight review May 1, 2002; seat: left; flight hours: 5,040 total, 228 in this make and model, 41 in the last 90 days, 31 in the last 30 days, 8 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 70 °F ## 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 20050804017489A](https://openairdocs.org/incident/20050804017489A), Aug 4, 2005: SAFARI, Leavenworth, WA, Substantial damage. (-23) After departing cashmere, WA, in cruise flight, a/c developed "buzz" and a momentary "yaw". PIC elected to make an autorotation to an open farmer's… 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.