# NTSB MIA96LA113: Snowbird 636D4, N7047J, Okeechobee, FL, April 10, 1996 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: April 10, 1996, 17:15 local (21:15 UTC) - Place: Okeechobee, FL - Coordinates: 27.500875, -80.929573 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=27.5009&lon=-80.9296&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 2 fatal - Status: Completed, report October 22, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 38003 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA96LA113 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/38003/pdf - Page: https://openairdocs.org/ntsb/MIA96LA113 ## Probable cause the failure of the main rotor control connecting rod, which rendered the control stick unusable and led to a loss of control. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, maneuvering - miscellaneous,bolt/nut/fastener/clamp/spring - disengaged - maintenance,installation - improper, other maintenance personnel - rotorcraft flight control system - disconnected (cause) - Loss of control - in flight, maneuvering - aircraft control - not possible, pilot in command - In flight collision with terrain/water, descent - uncontrolled ## Analysis The pilot had been experiencing vibrations in the gyroplane. The passenger/mechanic went with the pilot on this flight to help determine the cause of the vibration. At a cruise altitude of about 900 feet above the ground, the gyroplane was observed in a vertical descent until it impacted the ground. Examination of the wreckage revealed that the main rotor control connecting rod was broken at the rotor gear. Further examination revealed that the rear roll/pitch anchor point bolt for the control stick had worked loose and rendered the control stick unusable. ## Factual narrative On April 10, 1996, about 1715 eastern daylight time, a Snowbird gyroplane, N7047J, registered to a private owner, operating as a 14 CFR Part 91, personal, local flight, and crashed in the vicinity of Okeechobee, Florida. Visual meteorological conditions prevailed and no flight plan was filed. The gyroplane was destroyed, and the commercial pilot and one passenger were fatally injured. The pilot had been experiencing vibrations in the gyroplane. The passenger, a mechanic, went with the pilot on this flight to help determine the cause of the vibration. The flight was at a cruise altitude of about 900 feet above the ground, when the gyroplane was observed in a vertical descent until it impacted the ground. Examination of the wreckage revealed that the main rotor, control connecting rod, was broken at the rotor gear. Further examination revealed that the rear roll/pitch anchor point bolt, for the control stick, had worked loose, and rendered the control stick unusable. An autopsy was performed on the pilot, on, April 11, 1996, at the Medical Examiner's Office, in Fort Pierce, Florida, by Dr. Frederick P. Hobin. Toxicological tests were conducted at the Medical Examiner's Office, in Fort Pierce, Florida, and revealed "no drugs or alcohol." ## Aircraft - Registration: [N7047J](https://openairdocs.org/deregistered/N7047J-2013-07-10), registration cancelled 2013-07-10, S/N 5101 636D4, built 1994 (OpenAirDocs) - Reported make and model: SNOWBIRD 636D4 - Registry model: [Noack David L SNOBIRD 636D4](https://openairdocs.org/model/noack-david-l-snobird-636d4) (registry code 05623TV) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Gyroplane, amateur-built - Serial number: 5101 - Engines: CANADIAN AIR CAM 100 115 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Leroy Hardee - Airworthiness certificate: Special, Experimental (Special) - Departed: OBE ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 37; flight instructor, commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: front; toxicology performed; flight hours: 490 total ## Weather - Conditions: Visual (VMC), Day - Wind: 30° at 10 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 68 °F, dew point 48 °F - Altimeter: 30.00 inHg - Observed at: PBI, 10 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 19960410006739A](https://openairdocs.org/incident/19960410006739A), Apr 10, 1996: Amtr SNOBIRDXL, Okeechobee, FL, Destroyed, 2 fatal. Observed vertical descent to ground during test flight. Rotor control rod broke. Roll pitch anchor bolt came off. 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.