Past Service Bulletins - Best Approach?

WDD

Final Approach
PoA Supporter
Joined
Oct 16, 2019
Messages
6,179
Location
Atlanta / Marietta
Display Name

Display name:
Vintage Snazzy (so my adult children say)
What is a good, what is the common practice to make sure past Service Bulletins are not skipped. Some recent threads on missed past Service Bulletins and our club’s recent experience has prompted this question.

ADs are sent to the current owner and, and a list of current ADs can be found somewhat easily. Mechanics are also alerted.

Not so for Service Bulletins. They are sent to aircraft owner. What if a SB was sent 25 years ago, for example, to the owner before the previous owner, and he took action.

It would not be readily apparent to either owner or current mechanic that something was missed.

In our club’s case, what was missed 25 years ago was a change to working with a part in the nose gear that if fails prevents the gear from locking - which it did.

So, is it common practice to do an audit of the log books against all of the service bulletins? What is the best practice? How does one make sure they have a complete list of all SB?

Thanks!
 
Yes Audit away. I was hired at a major airline, as a temporary outside quality control auditor. Exact numbers I don't remember but there were about 120 airplanes and about 130 possible AD's applicable to any plane. Took 3 of us 4 months. Found AD's not complied with on airplanes less than 3 months out of the factory. Some others from long ago may have been done, but we could not find documentation. So they were pulled from service when we ran out of logbooks and couldn't find a record of their compliance so they could be done.
 
Lycoming publishes a list of service bulletins, letters and instructions that pertain to each engine family. https://www.lycoming.com/sites/default/files/attachments/SSP-112-13_Index_of_SB_SL_and_SI.pdf Unfortunately, the family is pretty broad. In my case, it includes O, IO, AEIO, TIO and LTIO-540s. I've worked my way through about half and found about ten that cover my specific engine. The next problem is that not all of them are available online. The shop has a subscription service (www.atp.com) that allows access. No idea what that costs, but I think that's the only way to access all of them.
 
So, is it common practice to do an audit of the log books against all of the service bulletins?
In what context? During a Part 91 scheduled inspection, no, unless requested by the owner.

What is the best practice? How does one make sure they have a complete list of all SB?
Most OEMs publish an SB/SL Index yearly or on a regulator basis and is usually free. Obtain those indexes and perform a survey of the mx record and aircraft. And this is definitely something an owner can perform. Just be sure to follow the model/serial number applicability of the SB/SL.
 
Good ideas and sources. And Jim brought into the light that there is separate list for airframes vs engine.
 
Good ideas and sources. And Jim brought into the light that there is separate list for airframes vs engine.
And propellers. And magnetos and vac pumps and all sorts of other "appliances."
 
This regulation should be printed on every aircraft 'Bill-Of-Sale'. It does not say that you do the maintenance. It says that you as Owner/Operator know what maintenance needs done and direct the mechanic. Other-words, you should join up with other Owners and "KNOW YOUR AIRCRAFT". 'Type Clubs' are essential to maintain +25 year old aircraft. Quite often the manufactures are not supporting old aircraft because there's no money in it. Don't wait on your IA to hold your hand and make the aircraft "Airworthy" that is the Owners responsibility. As you can read:

91.403 General.​


(a) The owner or operator of an aircraft is primarily responsible for maintaining that aircraft in an airworthy condition, including compliance with part 39 of this chapter.

If you ask for specific aircraft information to a group like POA you will get good answers and links to 'Service Information Resources'. Of course for a small annual fee most 'Type Clubs' have really good inventory of applicable Service Information.
 
  • Like
Reactions: WDD
And propellers. And magnetos and vac pumps and all sorts of other "appliances."
Where does one go to get all of these? Web sites, FAA, etc?

I’m starting from ground zero here.

Got to love this place for all the help and knowledge.
 
To start with look up Airworthiness Directives through the link below by putting your Aircraft, Engine, Propeller or Accessory "Model" number in the "Model" filter space. Check the box or boxes that reflects the Model you're looking for then click "Apply" box. Don't worry about entering any data in the other spaces just ignore them and use the "Model" space.


Ignition switches, Magneto and a couple other Accessories are by name not model. Just start typing Ignition or Magneto. Also type "Filter" in for air and oil filter A.D.s.
 
Where does one go to get all of these? Web sites, FAA, etc?

I’m starting from ground zero here.

Got to love this place for all the help and knowledge.
I started by making a component inventory spreadsheet of every "major" component on my aircraft. My list has avionics, antennas, mags, starter, alternator, solenoids, prop, cylinders, oil filter adapter, tires, wheels, seat belts, voltage regulator, battery, anything installed under an STC, etc.
I track Item, make, model/part #, serial #, description, overhaul/install date, overhauled/installed by, STC# (if applicable). It gets updated every time one of those components is removed/reinstalled/replaced. A physical copy stays in the plane.
Then you can use that to comb through ADs by manufacturer on the FAA website and SBs on the manufacturer's website. You can sign up for emails/notifications from some manufacturers.
It's a lot of work but worthwhile.

If you have a Cessna you can print off a Service Bulletins list of SBs applicable to your model, supposedly by S/N.

Also join type specific forums and associations to stay on top of things.
 
Where does one go to get all of these? Web sites, FAA, etc?

I’m starting from ground zero here.

Got to love this place for all the help and knowledge.
The manufacturer's websites. For instance, McCauley props: https://mccauley.txtav.com/en/service-bulletins

Amsafe seat belts/harnesses: https://www.amsafe.com/support/technical-documents/

United Instruments: https://www.unitedinst.com/

Marvel Schebler carburetors (including their predecessors Volare Carburetors LLC, Precision Airmotive Corporation, Facet Aerospace Products Company, Borg-Warner and the original Marvel-Schebler): https://msacarbs.com/technical-data/service-bulletins/

Sometimes one finds that an AD has been issued based on a Service Bulletin,

Because there are so many appliances, one will also often find components with unaddressed ADs. This includes United Instruments altimeters. I've have found that a couple of times. I've also found MANY times that the Bendix ignitions switch AD annual inspection has been carried out faithfully for 30+ years, but nobody ever got under the panel to see that it WAS a Bendix switch. It will often be an ACS ignition switch, affected by an entirely different AD, and is therefore way out of compliance. I would bet that among singles owned by POAers, 5 or 10% of them will have an ACS switch that has not had the AD inspections and mods done. Ever. The mechanics would rather assume it's a Bendix than do the contortions necessary to find out what brand it is. The ACS AD was issued in 1993. https://drs.faa.gov/browse/excelExternalWindow/B8ABD56539B4684886256A3E00759DBF.0001
 
Ah ….. this is going to be a lot more interesting. If I understand correctly for example, Cessna won’t have a SB for the seat belts it installed in its aircraft when it was made. I need to determine what brand if seatbelt I have and go to its website site. Or maybe the headliner manufacturer. Or the battery manufacturer.

Yeah - this will take a bit.

I assume airframe, engine, and prop are the critical manufacturers with which to start.
 
Considering for the last 20 years the Internet has been a thing, and it takes almost zero dollars to email a list of people, that the FAA would require any PMA entity to maintain a FREE subscriber list for updates to manuals, SBs etc.

No one a AOPA has thought of adding this to its lobbying agenda with the FAA?

After all, manufacturers complain about liability costs all the time, withholding SBs or updated documents of approved/acceptable date cannot be a good thing in a product liability case.
 
That is a million dollar idea right there.
 
Ref #13

I’ve actually had to pay the company to get the SB re an AD

on autopilot bridle clamps. It may have saved someone’s life though.

Might be easier with internal now.
 
The mechanics would rather assume it's a Bendix than do the contortions necessary to find out what brand it is.
Unfortunately, since the owner has the overall responsibility for AD compliance, its been known of them to not want to pay for a proper appliance AD survey during an annual or 100 hour. Have seen some interesting discussions on this down here.
 
Ah ….. this is going to be a lot more interesting. If I understand correctly for example, Cessna won’t have a SB for the seat belts it installed in its aircraft when it was made. I need to determine what brand if seatbelt I have and go to its website site. Or maybe the headliner manufacturer. Or the battery manufacturer.

Yeah - this will take a bit.

I assume airframe, engine, and prop are the critical manufacturers with which to start.
The airframe manufacturers will usually issue an SB regarding issues with stuff they didn't build but installed in the aircraft, sometimes in the form of a Service Letter, like so: https://cessnaowner.org/wp-content/uploads/2019/11/ourpdf-2.pdf
 
Unfortunately, since the owner has the overall responsibility for AD compliance, its been known of them to not want to pay for a proper appliance AD survey during an annual or 100 hour. Have seen some interesting discussions on this down here.
And yet, the annual requires inspections of "all systems," meaning that someone should be looking under that panel at the wiring and plumbing and instruments, including for signs of overheated connections due to loose hardware or corroded crimps, and that mag switch should be checked to see that its screws aren't loose. It takes three seconds to see if it's a Bendix or ACS.

But so often I've crawled under there and found not only an ACS switch, but rotted-out vacuum central and relief valve filters, cracked vac hoses, wiring and plumbing snagging on the controls as they move, burned crimp terminals on the landing light switch connections, and so on. Nobody is looking. And that's sometimes what the owner wants, alright. A cheap signature, as if that signature makes the airplane safe.
 
Dan; I don’t think it’s fair to say that “Nobody is looking”.

Some are and some aren’t. Just as some owners appreciate a good

inspection while others don’t.

We can probably write a good sized book with just “ under panel” findings.

Not uncommon on early Cessnas is to find the Artificial Horizon being

used as the UP- stop for the elevator control. Moving the yoke full

aft would result in banging on the instrument. Re-rigging of the

Elevator System is need in these cases.
 
And that's sometimes what the owner wants, alright. A cheap signature, as if that signature makes the airplane safe.
Exactly. And it was that attitude that eventually drove me to switch from ad-hoc to owner assist. Fortunately, I was able to make that switch where other shops could not.
 
Another factor is that often Techs do not do a good job of communicating what the task entails and why it is important.

The “Mechanically Declined”, who know very little about a task
often become experts regarding how little labor hours it takes.
 
Writing as an owner..., telling me that my aircraft is junk and the previous mechanics are bad doesn't help. Myself and other owners like @WDD are looking for solutions and best practices. I'm looking to you A&Ps with 50 years experience for advice not ridicule.

What should we do to make our +50 year old aircraft "Airworthy Condition"?
 
I thank God I was tutored by the previous owner of my airplane (also my A&P/IA until his death) who showed me the ropes over my first 10 years of ownership. Every owner assisted annual was worth 10 times what we paid.
Unfortunately, a lot of owners don't understand, and it's not taught, that they're in the driver's seat when it comes to maintenance and ownership, after all we're responsible for airworthiness.
The single best thing you can do is join type specific clubs/forums and dive in. Join them all at least for a while and find the ones that are still active and worthwhile. Read EVERYTHING. Forums, magazines, service letters/bulletins, ADs. Even maintenance topics not specifically related to your airframe are insightful. It's like drinking from a fire hose but all of your questions have been previously asked and answered somewhere, you just have to find it.

IMHO the Facebook ownership groups are absolute garbage. So many incomplete or wrong answers it's not even funny. You don't survive long on forums posting garbage answers like I see on Facebook. I see some of the turds that used to be on the various Cessna forums incorrectly answering questions on the Facebook groups.
I also think forums are a better medium for longer/more in depth/nuanced discussions & for reference (links/pictures) of important information on maintenance topics. Forums are easier to search and point to the answer/post when a question is repeated.
 
Last edited:
What should we do to make our +50 year old aircraft "Airworthy Condition"?
Be an engaged owner and maintain your aircraft in the spirit of Block 6 on the AWC. Also be proactive and work to make your entire aircraft meet its proper conformity and specification. This was the same mantra I used with my owner assist customers and can be applied to any owner who wants a better aircraft.
 
But so often I've crawled under there and found not only an ACS switch, but rotted-out vacuum central and relief valve filters, cracked vac hoses, wiring and plumbing snagging on the controls as they move, burned crimp terminals on the landing light switch connections, and so on. Nobody is looking. And that's sometimes what the owner wants, alright. A cheap signature, as if that signature makes the airplane safe.
A few weeks ago, I happened to notice the engine monitor reporting 70% power while descending on the base leg. After landing, it reported 50% power during the taxi to parking. After shutting down, I crawled under the panel and discovered a tee off of the manifold pressure line for the electronic ignition controller and what looked to be a rubber automotive-grade windshield washer hose joining them, which had pretty much rotted away.

Unless the deterioration happened over a period of a few months, it would appear that several someones were not looking.

And it should be noted, those signatures were quite the opposite of cheap.
 
Back
Top