

This guide is to help where Flight Data Recording Regulations, come into question for domestic aircraft transitioning to FAR Part 91 and 135 Operations, or a foreign aircraft imported into operations, under FAA registration.
Below is a High-Level view of both FAR Part 91 and Part 135 Operational requirements as it relates to FDR/DFDR requirements.
Reference Regulations
FAR 91.609 – Part 91 Operational Specifications
FAR 135.152 – Part 135 Operational Specifications
FAR 135 App E – Specific details FDR/DFDR conformity
FAR 25.1459 – Part 25 Installation Requirements
AC 20-141B – DFDR Advisory Circular
FAA Part 91 Operations or N Registered Aircraft Qualifiers:
- Greater than 10 Seats excluding Required Crew
- Multi Engine Turbine Powered
- Domestic Registered Aircraft
• FAR 91.609 applies by date of issuance of Initial Certificate of Airworthiness - Foreign Registered Aircraft
• FAR 91.609 applies by date of issuance of Initial FAA Import Certificate of Airworthiness
– Not aircraft’s initial date of Airworthiness Certificate
FAR 91.609 FDR/DFDR Requirements - Certificate of Airworthiness issue date:
- Before Oct 1991
• No requirement - Oct 1991 – Apr 2010
• 17 Parameter DFDR
• 8 Hour record time
- After Apr 2010
• 17 Parameter DFDR
• 25 Hour record time
• Underwater Locator Beacon
• TSO-124
FAA Part 135 Operations of N Registered Aircraft Qualifiers:
- 10 – 19 Seats excluding Required Crew
- Multi Engine Turbine Powered
- Domestic Registered Aircraft
• FAR 135.152 applies by date of issuance of Initial FAA Airworthiness Certificate
• Never under foreign registry - Foreign Registered Aircraft
• FAR 135.152 requirements applies by date of issuance of Initial FAA Import Certificate of Airworthiness
– Not aircraft’s initial date of Airworthiness Certificate
• Can receive FAA Import Certificate of Airworthiness under Part 91 as long as
FDR system complies with FAR 91.609
• Must be in conformity with 135.152 prior to Part 135 Certificate of Conformity
FAR Part 135.152 FDR/DFDR Requirements - Certificate of Airworthiness issue date:
- Prior to Oct 1969
• 11 Parameter FDR
• 8 Hours record time - Oct 1969 – Oct 1991
• 17 Parameter
• 8 Hours record time - Oct 1991 – Aug 2000
• 17 Parameter DFDR
• 25 Hour record time
• Underwater Locator Beacon - Aug 2000 – Aug 2002
• 57 Parameter DFDR
• 25 Hour record time
• Underwater Locator Beacon - After Aug 2002
• 88 Parameter DFDR
• 25 Hour record time
• Underwater Locator Beacon
- After 2010
• 88 Parameter DFDR
• 25 Hour record time
• Underwater Locator Beacon
• TSO-124A
Each OEM has paths for compliance for most airframes and there are aftermarket solutions on several airframes as well.
Please check with any of West Star’s Avionics Technical Sales Managers to determine path to compliance and availability.
For more Information, please contact:

Aaron Berg
Technical Sales Manager
Avionics (GJT)
Office 970.243.7500
Cell 970.261.6741

Josh Peterson
Technical Sales Manager
Avionics (CHA)
Office 423.661.8928
Cell 970.260.8332

Walt Marcy
Technical Sales Manager
Avionics (GJT)
Office 970.248.5258
Cell 970.234.9002

Mike Sichmeller
Technical Sales Manager
Avionics (ALN)
Office 618.258.8863
Cell 618.225.7587

John Brummel
Technical Sales Manager
Avionics (ALN)
Office 618.258.8065
Cell 618.225.9678