In-Flight Breakup of Bell 525 Relentless Helicopter
NTSB Aircraft Accident Reports · Accident report · AAR-19/02 · Published 2019-09-17 · National Transportation Safety Board · 1 author
Abstract and citation only, verbatim from NTSB Aircraft Accident Reports; full text lives there. All credit to the authors and National Transportation Safety Board.
Abstract
Bell 525 prototype helicopter in-flight breakup near Italy, TX, July 6, 2016 — 2 fatalities. Investigation of the developmental-flight-test in-flight breakup of a Bell 525 Relentless prototype. NTSB found a 6 Hz vibration filter interaction with the pilot biodynamic feedback caused divergent collective control inputs that exceeded the structural limits. Findings drove changes to FAA flight test certification programs and OEM human-vehicle coupling analysis requirements.
Author
- National Transportation Safety Board NTSB
Keywords
- flight test
- biodynamic feedback
- rotorcraft certification
- pilot induced oscillation
Citation
National Transportation Safety Board (2019). In-Flight Breakup of Bell 525 Relentless Helicopter. National Transportation Safety Board. NTSB Aircraft Accident Reports ID AAR-19/02. https://www.ntsb.gov/investigations/AccidentReports/Pages/AAR1902.aspx ↗