Airworthiness Directives, Designees & the PMA Crisis: A Candid Look at GA Regulation with Jimmy Tubbs
Aviation MastersShow Notes
In this return appearance on Aviation Masters, Mike Busch sits down again with legendary aeronautical engineer Jimmy Tubbs for a deep, technically rich conversation about the regulatory machinery that shapes general aviation.
From the flawed criteria behind Airworthiness Directives to the erosion of Designated Engineering Representatives, and from PMA approval delays to the disappearance of the Small Airplane Directorate's collaborative processes, Jimmy pulls back the curtain on how the system is supposed to work, where it breaks down, and what it costs aircraft owners and the GA community.
This is a candid, experience-driven conversation with one of the most knowledgeable engineers in piston aviation — essential listening for anyone who owns, operates, or maintains a GA aircraft.
⏱ Chapters 00:00 – Introduction & Jimmy's Background 03:00 – What Is an Airworthiness Directive & How Are They Triggered? 07:00 – The Two-Variable Framework: Frequency vs. Severity of Failure 11:00 – Why AD Analysis in GA Lacks Formal Criteria 17:00 – FAA Reorganization: The Loss of Directorates & Senior Engineers 21:00 – The ECI Cylinder AD: Head-to-Barrel Separations & Overreach 28:00 – Corrective Actions That Ignore Supply Chain Reality 31:00 – Short-Wing Piper Rudder AD & the Vintage Aircraft Association Fight 36:00 – Cessna 402 vs. 414 Spar Strap AD: When Scope Goes Too Far 41:00 – What Is an AMOC & How Can It Help Aircraft Owners? 43:00 – The Global AMOC: Continental's V-Band Clamp Solution 47:00 – The Airworthiness Concern Sheet: A Better Way That's Now Gone 53:00 – Twin Cessna Exhaust AD: How Industry Input Saved the Fleet 57:00 – DERs, ODAs & the 2025 Policy Shift Affecting Designee 1:05:00 – The PMA Approval Process: Slower & More Cumbersome Than Ever 1:10:00 – Why PMA Parts Are the Lifeline for Aging GA Aircraft 1:19:00 – The NORSEE Process: A Rare Bright Spot in FAA Approvals 1:22:00 – The Need for Young Engineers & the Future of the Aging Fleet 1:27:00 – Final Thoughts: Lobbying for a Better AD Process
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