For the past couple of years, the Cirrus community has been deeply engaged with Airworthiness Directive 2024-09-09 addressing turbocharged exhaust V-band clamps, specifically, the lack of readily available replacements. Just a couple of weeks ago, the issue came up during the opening banter on the Ask the A&P podcast that I co-host with Colleen Sterling and Mike Busch. We were lamenting yet another hit to fleet dispatch reliability, with no supply chain solution in sight. Little did we know that just days after that recording, the V-band universe would shift in a big way.
Since the mid-1970s, V-band clamps have been a persistent trouble spot for the turbocharged piston fleet. A quick review of the FAA’s background information for AD 2023-09-09 shows that since 1974, exhaust V-band coupling issues have resulted in seven NTSB Safety Recommendations, 10 FAA Special Airworthiness Information Bulletins, and 10 Airworthiness Directives. Having worked through all of these over the years, it’s striking how little the basic construction of these couplings has changed, until now.
Two New Solutions
Continental Motors issued Service Letter SIL26-02 on March 11, announcing the availability of a riveted V-band clamp (p/n 672127) to replace the spot-welded version (p/n 653332). Installation of this new clamp would constitute terminating action for AD 2023-09-09, eliminating the reoccurring inspection and replacement requirements. A copy of SIL26-02 included with this article illustrates the differences between the two designs. Hopefully, by the time you read this, these new clamps are actually making it into the supply chain.
Hartzell has also entered the mix with its AeroForce V-band clamps for Continental and Lycoming engines, and this design takes a notably different approach. Instead of traditional V-sections attached to a band with a tightening bolt, Hartzell uses cables to transfer the clamping force to the V-sections. Cables, being inherently unruly, require some discipline so the design incorporates tabs and safety wire to keep everything in line. The result is a clamp with a very distinctive appearance. I can’t help but think Dr. Frankenstein had a hand in design of this “Frankenclamp.” Only time will tell if this creation can handle the fire of holding our turbo exhaust systems together.
photo from Hartzell
At the typical flying rate of 100 hours per year, many owners are still a couple of years away from the 500 hour mandatory replacement of the spot welded clamps that AD 2023-09-09 refers to. Annual inspections may continue on those for now. Eventually, everyone will be installing new V-band clamps of some sort. Regardless of which solution one chooses, at least we have some comfort that remedies are on the way.
© 2026 Paul New
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