Piper Service Bulletin SB1377

This just in from Piper on January 24, 24.


Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
Aviation Director, Piper Owner Society Forum Moderator and Pipers Author.

Need help? Let me know!


  • edited January 24

    The next service bulletin will be inspecting for corrosion on the main spar in the area where paint was chemically removed in SB_1377 and the paint remover wicked into the spar assembly....

    Eric Panning
    1981 Seneca III
    Hillsboro, OR (KHIO)

  • Perhaps you'd like some of my proprietary etchant, which removes the paint while totally benign to 2024, 6061 and 7075. Available today at the low introductory price of 30K/pint!


  • Order the pint now and delivery expected in 2025. Comes with a free exhaust clamp and free shipping. ;)

    Seriously - this SB is probably best done at your hanger during annual time. If there are any issues the delays could be extensive. Also some findings would require NDT bolt hole inspection similar to spar bolt hole inspection. This requires equipment, inspector and it is possible to mess up the inspection and judge the spar as damaged.

    Eric Panning
    1981 Seneca III
    Hillsboro, OR (KHIO)

  • How about if it came to you with a factory AME who had performed the SB hundreds of times, so he/she could do in flawlessly in his sleep. And both will arrive on the company Meridian.

    We should have more of these brainstorming sessions!

  • How about a loaner Meridian if this inspection grounds our plane.

    Ok, so we do this just once at 2000 hours, and then, magically, it can never resurface, at any point in the future?

    If it was important enough to create a SB regarding a stress point, seems that this should have some data driven frequency.

  • I don't think they leave open the possibility to drill oversize for the boat hole if a potential crack is detected. I would want to drill to the max allowed and then re-inspect.

    Would be great if they had frequency of occurrence and any known issues for the fleet today. It seems the purpose is to generate the data on mostly the non Part 91 fleet that has to follow CSB's and see if there is an actual issue.

    The possibility of inspection related damage here is high....

    Eric Panning
    1981 Seneca III
    Hillsboro, OR (KHIO)

  • If a loaner Meridian was in the mix, the failure rate for piston retractables would be 100% ! Starting with mine...

    There's an interesting FAA webinar running periodically, called "Managing the Aging Fleet." SB1377 is what they call a Surveillance Service Bulletin, or SSB, and just like Eric says, the purpose is to determine the prevalence of truss bracket land cracks within the fleet, now that a single incident was identified in a routine inspection. Future ADs and SBs will depend upon results from the SSB data collection, and could potentially be recurrent like jacobsja says.

  • I was just happy that (for once!) my plane was NOT on the "affected aircraft" list. Might be a first!

    Then I read all your responses. 🤣🤣🤣

    Your comments are pure gold, and made my day!

    Jim "Doc Griff" Griffin
    PA28 - 161
    Chicago area

  • Reading between the lines- they mention assessing flush rivets for any that are proud of the surface and grinding them back down. That's weird if we are looking for bolt holes starting to crack in the spar. I suspect a plane had some rivets under the truss not truly flush. This caused the truss to not be flush to the spar when they torqued it and resulting movement caused bolt hole enlargment, and weakening/cracking. Now Piper wants to know how many spars were built incorrectly, and they're doing so on our backs with this SB.

  • Tokirbymd - Yes, that is my read too. I have bucked plenty of rivets when building an experimental RV-10 and I would never grind down a rivet as they are easy to replace. There is a tool for shaving them but I am not convinced this is a good path for a rivet in the spar.

    Eric Panning
    1981 Seneca III
    Hillsboro, OR (KHIO)

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