FTW98LA211
1998-05-09 · FALCON, Colorado, United States · Serious · 1 aircraft · Status: Completed
Aircraft involved
Probable cause & findings
The vibration induced overload failure of the canopy holdback fitting resulting in reduced control capability. A factor was partial failure of one propeller blade for unknown reasons.
Factual narrative
On May 9, 1998, at 1400 mountain daylight time, an experimental Eller BD-5B, N194EC, impacted terrain when the canopy partially separated during a test flight near Meadow Lake Airport, Falcon, Colorado. The airline transport certificated pilot, and sole occupant, received serious injuries and the aircraft sustained substantial damage. No flight plan was filed for this local area flight operating under Title 14 CFR Part 91. Visual meteorological conditions prevailed. According to the pilot, he had conducted glide and power off stall tests and was making a low pass in the pattern when the aircraft began a violent vibration and involuntarily entered a left turn. The pilot said he corrected the turn and the canopy partially separated due to vibration. Due to the drag from the canopy, the pilot had to maintain a 20 to 35 degree nose down attitude to prevent the aircraft from entering a stall. He said he raised the nose and entered a full stall condition just prior to impact with the ground. Examination of the aircraft by an FAA airworthiness inspector provided evidence of a crack in one blade of the wood propeller between 15 and 18 inches inboard from the blade tip. The blade was sent to the National Transportation Safety Board Materials Laboratory for examination. The laboratory report is attached and states that the blade contained no obvious area of mechanical damage but was cracked about one half to two thirds through the cross section of the blade arm. The laboratory examination found no evidence of weakness in the wood and no evidence of inadequate bonding between the plies of wood. The aircraft examination also provided evidence that the canopy holdback fitting was fractured. The fitting was removed and it was also sent to the Materials Laboratory for examination. The laboratory report is attached and states that the fracture faces were typical of overstress. The propeller and canopy holdback fitting were returned to the owner/builder following examination. While on a local test flight, the aircraft developed a violent vibration and the canopy partially separated causing control of the aircraft to be reduced. To prevent a stall the pilot had to maintain an exaggerated nose down attitude with the aircraft and conducted a full stall hard landing short of the runway. Postcrash examination revealed that one of the wooden propeller blades had cracked. The examination did not provide any evidence that would have caused the blade strike, weakness in the wood, or inadequate laminate bonding. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_1998_FTW98LA211.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 (stall). All research papers
- NASA NTRS 2026 · Conference Paper Computational Analysis of Steady State Aerodynamics of Transonic Truss-Braced Wing Configuration in Deep Stall
This study presents a computational investigation of steady state aerodynamics of the Subsonic Ultra-Green Aircraft Research (SUGAR) Transonic Truss-Braced Wing (TTBW) configuration over a wide range …
- arXiv 2023 · arXiv preprint Automating Bird Diverter Installation through Multi-Aerial Robots and Signal Temporal Logic Specifications
This paper tackles the task assignment and trajectory generation problem for bird diverter installation using a fleet of multi-rotors.
- arXiv 2023 · arXiv preprint Variation of Critical Crystallization Pressure for the Formation of Square Ice in Graphene Nanocapillaries
Two-dimensional square ice in graphene nanocapillaries at room temperature is a fascinating phenomenon and has been confirmed experimentally.
- arXiv 2023 · arXiv preprint Polycrystallinity enhances stress build-up around ice
Damage caused by freezing wet, porous materials is a widespread problem, but is hard to predict or control. Here, we show that polycrystallinity makes a great difference to the stress build-up process…
- arXiv 2022 · arXiv preprint Enhanced Prediction of Three-dimensional Finite Iced Wing Separated Flow Near Stall
Icing on three-dimensional wings causes severe flow separation near stall. Standard improved delayed detached eddy simulation (IDDES) is unable to correctly predict the separating reattaching flow due…
- Embry-Riddle Scholarly Commons 2021 · Journal article (JAAER) Analysis on the Negative Emotional, Physiological, and Cognitive Responses Elicited from of the Activation of a Stall Alarm
Failing to identify an aerodynamic stall can lead to the inability of an aircraft to sustain flight. To warn pilots of an impending or fully-developed stall, many aircraft have safety devices installe…