# NTSB FTW98LA211: Eller BD-5B, N194EC, Falcon, CO, May 9, 1998 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: May 9, 1998, 14:00 local (20:00 UTC) - Place: Falcon, CO - Coordinates: 39.030372, -104.480636 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.0304&lon=-104.4806&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report March 31, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 20599 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW98LA211 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/20599/pdf - Page: https://openairdocs.org/ntsb/FTW98LA211 ## Probable cause 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. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, maneuvering - turn to landing area (emergency) - propeller system/accessories,blade - cracked (contributing factor) - reason for occurrence undetermined - miscellaneous,bolt/nut/fastener/clamp/spring - overload (cause) - aircraft control - reduced - Loss of control - in flight, descent - emergency - In flight collision with terrain/water, descent - uncontrolled ## Analysis 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. ## 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. ## Aircraft - Registration: [N194EC](https://openairdocs.org/deregistered/N194EC-2000-04-26), registration cancelled 2000-04-26, S/N 1994 (OpenAirDocs) - Reported make and model: Eller BD-5B - Registry model: [Eller Richard E BD-5B](https://openairdocs.org/model/eller-richard-e-bd-5b) (registry code 11307N9) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 1994 - Airframe hours: 12 - Engines: Suzuki 635CC 65 horsepower reciprocating - Damage: Substantial damage - Flight: Part 91 - Registered owner: Eller Construction, Inc. - Airworthiness certificate: Special, Experimental (Special) - Departed: 00V ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; airline transport, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; seat: front; flight hours: 4,477 total, 2 in this make and model, 4,477 as pilot in command, 23 in the last 90 days, 5 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 59 °F - Altimeter: 29.00 inHg - Observed at: COS, 12 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 19980509015359A](https://openairdocs.org/incident/19980509015359A), May 9, 1998: Amtr BD5B, Falcon, CO, Substantial damage. Low pass over runway. Canopy blew off. Lost control. Crash landed. (.4)while on a local test flight, the aircraft developed a violent vibration and the canopy… 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.