SEA95LA223
1995-09-23 · CRATER LAKE, Oregon, United States · Fatal · 1 aircraft · Status: Completed
N6099Z has since been reassigned. It is now registered to a different aircraft (CIRRUS DESIGN SR22), which was not involved in this event.
Aircraft involved
Probable cause & findings
FAILURE OF THE PILOT TO MAINTAIN SUFFICIENT ALTITUDE/CLEARANCE ABOVE WATER, WHILE PERFORMING LOW ALTITUDE FLIGHT. FACTORS RELATING TO THE ACCIDENT WERE: THE GLASSY WATER CONDITION, AND LACK OF VISUAL CUES CONCERNING PERCEPTION OF ALTITUDE.
Factual narrative
On September 23, 1995, at 0925 Pacific daylight time, N6099Z, a Eurocopter AS350BA, operated by the manufacturer, collided with water while descending over Crater Lake, Oregon, and was destroyed. The airline transport helicopter demonstration pilot and his passenger were fatally injured. Visual meteorological conditions prevailed and no flight plan had been filed. The business flight departed from Aurora, Oregon, about 0830 and was conducted under 14 CFR 91. One day prior to the accident, on September 22, 1995, the pilot departed from Seattle, Washington, en route to Aurora. According to a line service person and local authorities, the pilot was the sole occupant of the helicopter during this flight, and he stayed overnight in Aurora to visit friends before flying to Las Vegas, Nevada, on the following day. The purpose of the flight to Las Vegas was to display the helicopter at a business aviation convention. According to a line service person at the Aurora Airport, the helicopter arrived about 1400 and landed near a fuel truck. The line service person fueled the aircraft with 76 gallons of jet fuel and spoke briefly to the pilot. The line service person stated that the pilot was alone and "seemed fine." The pilot made a telephone call and was picked up by an unidentified man. The next morning, the day of the accident, the pilot returned to the airport between 0800 and 0900. The line service person stated that the pilot "seemed fine" and was accompanied by two other unidentified men. Although the line service person did not see the helicopter depart, he assumed that one of the two men accompanied him on the flight. The line service person also stated the pilot made no mention of his intended flight, nor did he report any mechanical difficulties with the helicopter. About 0925, the helicopter was observed by numerous witnesses (statements attached) maneuvering at a "low" altitude over Crater Lake National Park. The witnesses reported that the helicopter circled around Wizard Island beneath the caldera of the lake and was headed in an easterly direction, into the sun, at the time it impacted the water. No unusual engine noises or erratic movements were reported. Upon impact, the helicopter broke apart and sank. According to one eyewitness who was hiking near the shore of the Lake: The helicopter was flying in a general east-to-west direction, approx. 1/4 of the caldera height up from the water surface. The helicopter was flying at speed that was not overly fast or slow. The sound of the engine was constant, and appeared to be in no distress. The craft continued its flight toward Wizard island.... The helicopter made a gentle turn.... At no point did the helicopter slow down or look like he may possibly try to land on the island. His elevation had stayed about the same. I estimate that 150 - 300 feet off the water. The engine sound continued to be strong and constant. As the helicopter passed the east end of Wizard Island I noticed that due to glassy blue waters of the lake, and bright blue skies, this all white helicopter was making a beautiful perfect image in the water. I could see the helicopter and its reflection coming nearly directly toward me. When I first noticed the reflection [of the] helicopter it was flying fairly level, then gradually started a very gentle decent. As I continued to watch I noticed the helicopter and its reflection becoming closer together. As the helicopter became closer to the water the distance between it and [its] refection was less. This flight pattern continued for at least 1 1/2 minutes until the helicopter crashed into the lake. At no point did the helicopter try to alter its flight pattern, descent rate, or attempt to gain elevation. As I watched the helicopter hit the water the engine noise was still very strong, with no sound of problems. The engine sound continued after the helicopter crashed and tumbled over. According to the operator, the helicopter was manufactured on March 15, 1994, received an FAA Certificate of Aircraft Registration on April 18, 1995, and a Standard Airworthiness Certificate on August 30, 1995. The helicopter had accumulated about 28 flight hours since its last inspection. An examination of the helicopter's maintenance records did not reveal any evidence of unresolved discrepancies. The helicopter was owned and operated by the manufacturer and was used as a demonstrator model for sales purposes. It was based in the Seattle area at the accident pilot's residence. The pilot, age 51, was a rated airline transport pilot with a rating for rotorcraft-helicopter. According to the operator, the pilot had accumulated about 10,000 flight hours, including over 1,000 hours in type. The pilot was issued an FAA Second Class Medical Certificate on September 15, 1994, with the restriction that he "must wear glasses for near and distant vision." Officials with the Crater Lake National Park estimate that the majority of the helicopter wreckage and both occupants are currently under 1,500 feet of water. The officials also stated that salvage efforts have not been attempted. Pieces of light- weight debris were found floating near the impact site and were recovered. The debris included a door, outer body panels, rotor blade pieces, seat cushions, and a cowling. The pilot was employed by a helicopter manufacturer as a demonstration pilot. He and a passenger departed on a flight to attend a business aviation convention. Along the route, the pilot was observed by numerous witnesses to perform low altitude flight maneuvers over a lake in a national park. While the helicopter was flying less than 300 feet over the surface of the lake, witnesses observed that it gradually descended in a shallow glidepath at cruise speed until it impacted the surface. The engine was reported to be providing power at the time of impact. No indication of mechanical failure was noted. The helicopter was flying toward the sun and over glassy water conditions at the time of impact. Neither it nor the occupants were retrieved. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_1995_SEA95LA223.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
Search this event elsewhere
External sources are reported, not agency: signal that something happened, not fact about what happened.
- TallyAero Live Wire Aviation press
- NTSB CAROL Agency ↗
- NTSB Docket Agency ↗
- Aviation Safety Network Aviation press ↗
- Kathryn's Report Aviation press ↗
- Aviation Herald Aviation press ↗
- AVweb Aviation press ↗
- Pilots of America Community ↗
- Reddit /r/flying Community ↗
- FlightAware Aviation press ↗
- AOPA accident database Aviation press ↗
- Google News News ↗
- DuckDuckGo News ↗
Related research
Matched on aircraft type or causal vocabulary (maintenance). All research papers
- Embry-Riddle Scholarly Commons 2026 · Journal article (IJAAA) From Reactive to Predictive: A hybrid Trust-Mediated Adoption Framework for Data-Driven Maintenance in Distributed-Authority Aviation Environments
Modern aviation maintenance operates within increasingly data-intensive technological environments, yet the operational integration of predictive maintenance into routine decision-making remains incon…
- Semantic Scholar 2026 · Article (Reliability Engineering & System Safety) Understanding human error in military aviation maintenance: The role of Performance shaping factors, cognitive workload and error orientation
- Semantic Scholar 2025 · Article (Applied Sciences) Decision-Making Framework for Aviation Safety in Predictive Maintenance Strategies
The implementation of predictive maintenance (PM) in aviation presents unique challenges due to strict safety requirements, complex operational environments, and regulatory constraints.
- Semantic Scholar 2024 · Article (Defence Science Journal) Modelling of Human Factors in Aviation Maintenance Using HFACS ME Human Factors Analysis and Classification System Maintenance Extension and Bayesian Network
Aircraft maintenance is a complex task involving a skilled human workforce, spare parts, and various other resources. Human factors are an inherent element of the human workforce.
- Embry-Riddle Scholarly Commons 2024 · Journal article (JAAER) A New Trajectory in UAV Safety: Leveraging Reinforcement Learning for Distance Maintenance Under Wind Variations
In the field of aviation, safety is a critical cornerstone, and the operation of Unmanned Aerial Vehicle (UAV) systems is deeply connected with this principle.
- Embry-Riddle Scholarly Commons 2024 · Journal article (JAAER) Low-Resource Automatic Speech Recognition Domain Adaptation – A Case-Study in Aviation Maintenance
With timeliness and efficiency being critical in the aviation maintenance industry, the need has been growing for smart technological solutions that optimize and streamline the different underlying ta…