The Back Door is Locked

Cessna 210In my AOPA Opinion Leaders Blog post of September 2014 (“Backdoor Rulemaking?”), I discussed the unprecedented action taken by the Cessna Aircraft Company intended to compel the owners of cantilever-wing Cessna 210s to perform repetitive eddy-current inspections of their wing spars. Finally, I can fill you in on the punch line.

By way of background: Normally, if an aircraft manufacturer believes that an unsafe condition exists that justifies imposing special inspections, component life limits, replacement or overhaul times, or similar burdens on aircraft owners, they go to the FAA and ask for an Airworthiness Directive (AD) to be issued. If the FAA is persuaded that the alleged unsafe condition actually constitutes a significant safety concern and that the burden on owners is reasonable given the safety risk, then the FAA issues a Notice of Proposed Rulemkaing (NPRM) announcing its intention to issue an AD and soliciting comments on the proposal from the affected public. The FAA is then required to consider and respond to all public comments submitted during the comment period before issuing its final rule that makes the AD effective. This same notice-and-comment protocol is required of all executive-branch regulatory agencies of the U.S. federal government by a law called the Administrative Procedure Act (APA).

Indeed, that’s precisely what Cessna did in 2013: It asked the FAA’s Wichita Aircraft Certification Office (ACO) to issue an AD mandating repetitive eddy-current inspections on all cantilever-wing Cessna 210s. But to Cessna’s chagrin, the Wichita ACO turned down Cessna’s request and declined to proceed with an AD, presumably because the ACO was not persuaded that such an AD was justified.

That should have been the end of the matter. But it wasn’t.

In February 2014, Cessna very quietly published a revision to the Cessna 210 service manual that added three new pages to the manual. Those three pages constituted a new section 2B to the manual, titled “Airworthiness Limitations,” that called for the repetitive eddy-current spar inspections. Somehow Cessna persuaded the Wichita ACO to approve this amendment—something the ACO really shouldn’t have done, as you shall see.

Cessna then publicly took the position that compliance with the repetitive eddy-current spar inspections was compulsory because those inspections were now part of an FAA-approved Airworthiness Limitations Section (ALS). Indeed, FAR 91.403(c) compels aircraft owners to comply with mandatory replacement times, inspection intervals, and related procedures specified in an ALS. And FAR 43.16 compels maintenance personnel to perform any inspections or maintenance specified in an ALS precisely “by the book.”

David vs. Goliath?

SlingshotI first learned about this at the beginning of September 2014, when my colleague Paul New—owner of Tennessee Aircraft Services, Inc. (a well-known Cessna Piston Aircraft Service Center) and honored by the FAA in 2007 as National Aviation Maintenance Technician of the Year—discovered the new section 2B in the Cessna 210 service manual, and immediately realized its significance. Paul and I discussed the matter at length, and both felt strongly that Cessna’s actions could not be allowed to go unchallenged.

“If Cessna gets away with this,” I told Paul, “then any manufacturer will be able to effectively impose their own ADs whenever they want, bypassing the notice-and-comment protocol and the other safeguards built into the APA to protect the public from unreasonable government regulation.”

I helped Paul draft a letter to the Rulemaking Division (AGC-200) of the FAA’s Office of General Counsel, questioning the retroactive enforceability of Cessna’s newly minted ALS against Cessna 210s that were manufactured prior to the date the ALS was published (i.e., all of them, given that Cessna 210 production ceased in 1986). Our letter questioned whether Cessna could do what it was trying to do (i.e., make the eddy-current inspections compulsory) within the confines of the APA. We asked AGC-200 to issue a formal Letter of Interpretation (LOI) of the thorny regulatory issues that Cessna’s unprecedented actions raised.

And then we waited. And waited.

AGC-200 initially advised us that they had a four-month backlog of prior requests before they would be able to respond to our request. In fact, it took seven months. It turns out that our letter questioning the enforceability of Cessna’s ALS opened a messy can of worms. AGC-200 assigned two attorneys to draft the FAA’s response, and they wound up having to coordinate with AFS-300 (Flight Standards Maintenance Division), AIR-100 (Aircraft Certification Division), ACE-100 (Small Airplane Directorate), and of course ACE-115W (Wichita Aircraft Certification Office) who mistakenly approved Cessna’s ALS in the first place.

FAA Legal Does the Right Thing

FAA Headquarters

FAA Headquarters
800 Independence Ave.
Washington DC

Finally, on May 21, 2015, AGC-200 issued the Letter of Interpretation (LOI) that we requested. It was five pages long, and was everything we hoped it would be and more. It slammed shut the “rulemaking backdoor” that Cessna had been attempting to use to bypass the AD process, locked it once and for all, threw away the key, and squirted epoxy glue in the lock for good measure. You can read the entire LOI in all its lawyerly glory, but here’s the CliffsNotes version of the letter’s key bullet points:

  • Under FAR 21.31(c), an ALS is part of an aircraft’s type design.
  • The only version of an ALS that is mandatory is the version that was included in the particular aircraft’s type design at the time it was manufactured.
  • Absent an AD or other FAA rule that would make the new replacement times and inspection intervals retroactive, Cessna’s “after-added” ALS is not mandatory for persons who operate or maintain the Model 210 aircraft, the design and production of which predate the new ALS addition. The “requirements” set forth in the ALS would only be mandatory for aircraft manufactured after the ALS was issued. And of course, production of the Cessna 210 ceased in 1986.
  • If operational regulations were interpreted as imposing an obligation on operators and maintenance providers to comply with the latest revision of a manufacturer’s document, manufacturers could unilaterally impose regulatory burdens on operators of existing aircraft. This would be legally objectionable in that the FAA does not have legal authority to delegate its rulemaking authority to manufacturers. Furthermore, “substantive rules” can be adopted only in accordance with the rulemaking section of the APA (5 U.S.C. § 553) which does not grant rulemaking authority to manufacturers. To comply with these statutory obligations, the FAA would have to engage in its own rulemaking to mandate the manufacturer’s document, as it does when it issues ADs.

The bottom line is this: Manufacturers of certificated aircraft* are not permitted to impose regulatory burdens on aircraft owners by changing the rules in the middle of the game. Only the FAA may do that, and only through proper rulemaking action that complies with the APA (including its notice-and-comment provisions and other safeguards). If you ever encounter a situation where the manufacturer of your aircraft tries to do this, call their cards—the FAA lawyers will back you up.

*NOTE: The rules are completely different for S-LSAs.  The manufacturers of S-LSAs can do pretty much anything they like, and their word is the law. (A seriously flawed situation IMHO.)

The LOI concluded with the following surprising paragraph:

On February 19, 2015, the FAA’s Small Airplane Directorate sent a letter to Cessna that addressed some of the above issues, and pointed out the non-mandatory nature of the after-added ALS for the Model 210 aircraft. The FAA asked Cessna to republish the replacement times and inspections as recommendations that are encouraged, but optional, for those in-service aircraft, unless later mandated by an AD. To date [three months later –mb] Cessna has not provided a written response outlining its position on this matter.

Are we having fun yet?

Mike Busch is arguably the best-known A&P/IA in general aviation, honored by the FAA in 2008 as National Aviation Maintenance Technician of the Year. Mike is a 8,000-hour pilot and CFI, an aircraft owner for 50 years, a prolific aviation author, co-founder of AVweb, and presently heads a team of world-class GA maintenance experts at Savvy Aviation. Mike writes a monthly Savvy Maintenance column in AOPA PILOT magazine, and his book Manifesto: A Revolutionary Approach to General Aviation Maintenance is available from in paperback and Kindle versions (112 pages). His second book titled Mike Busch on Engines was released on May 15, 2018, and is available from in paperback and Kindle versions. (508 pages).


  1. A rare win for the good guys! Thanks for fighting the good fight Mike…

  2. All of this begs the question: Are eddy current inspections a sound recommendation, or is Cessna trying to ground older aircraft by driving the cost of ownership up?

    • Liberal in CA

      June 15, 2015 at 7:21 pm

      If the inspection were critical, why would Cessna go about it in such a subtle way? The method they chose ensured many if not most aircraft owners and maintenance folk were not aware of the “need”. There are better means, including the FAA program to issue maintenance alerts that fall short of the criteria for AD issuance. If Cessna has a sound technical basis, they should have shared that openly. It would seem irresponsible to have done otherwise.

    • IMHO, the eddy-current inspections that Cessna is calling for are reasonable and prudent, but the way they went about trying to make them compulsory on aircraft owners was unacceptable and needed to be challenged.

  3. Liberal in CA

    June 15, 2015 at 7:12 pm

    This will all be solved with the FAAs revision of light aircraft certification which, as proposed by the FAA, would follow the “light sport” rules which empower the manufacturer to be the sole authority as to what is required for continued airworthiness. As with the light sport system now, there would be no public process for review or comment. Many a light sport owner has been caught in this trap even when the manufacturer had great intentions but ceased to exist.
    This is IMO a huge problem with the FAA’s proposed “overhaul” of the light aircraft certification rules. While there is much that could be improved, the proposed move towards the SAE/Light Sport is not a good move.

    • That would be a disaster. I hope all aircraft owners will unite in fighting against the “consensus standards” concept that would put manufacturers in the drivers seat (as is currently the case with LSAs). If this happens, I think it likely that the legacy GA fleet (like the 1979 Cessna 310 I fly) will wind up on the ground. –Mike

  4. Butch Gilbert

    June 15, 2015 at 7:17 pm

    Mike Busch, you continue to be a real hero to all pilots, owners and mechanics. I think your blog (which I have read every one) is one of the most important, informative and educational pieces of literature in all of General Aviation. Thank you.

  5. My thoughts immediately went to the same situation on the Pilatus Porter PC-6. I had to turn down purchase of an otherwise good airplane because Pilatus’ ALS is so horribly burdensome that the plane nearly needs rebuilding every few years and this particular bird I was considering hadn’t been kept in compliance. What a win! I should probably try to find and buy that plane again… Has anyone dealt with this one before?

  6. Mike, Thank you to you and Paul for taking this on. It also shows that the FAA is, as I have often thought is a split personality organization, some of them really do want us to keep flying.
    Liberal in CA, I agree with you in that the re-write of prt. 23 could go very badly. It is quite possible that living within the existing rules could be better than the seemingly simple “consensus standards” that can change quickly and with out outside oversight.

    • In my opinion, the whole “consensus standards” concept (like what was done for LSAs) is a complete disaster. It puts the manufacturers in the drivers seat instead of the FAA. And the manufacturers interests are definitely NOT coincident with the interests of the aircraft owners…especially for an out-of-production model like the Cessna 210. –Mike

  7. Sadly I suspect Cessna’s actions were driven by their lawyers trying to deal with the glut of over-the-top injury/loss of life lawsuits and resulting astronomical jury awards. The logic now would be – No inspection, therefor poor maintenance, therefor pilot/owner’s negligence, therefor grounds to limit award to a smaller number.

    Our out of control tort system is behind many of these “unintended consequence” actions. When I purchased a new C172R in 1998 (for the princely sum of $144k !) I was told by a Cessna rep that over 30% of that price was their “set aside” for future lawsuits. Now that the same airplane is being sold for over $450k (quite frankly insane since costs/materials/pay checks have not tripled in 15 years) I shudder to think what percentage represents a reserve for future legal hassles. Remember, Cessna shut down ALL their single engine production lines for years as a result of the out of control tort system and only re-started when the 18 year “liability limitation” was enacted.

    • I’m less cynical about this than you, Gary. Fact is that there has never been an accident or even a close call caused by wing spar cracking of the kind the proposed eddy-current inspections are intended to detect. I think that what Cessna was proposing was reasonable, but the way they went about trying to make it mandatory wasn’t.

  8. Evan Mortenson

    June 20, 2015 at 4:09 am

    Mike, this might be a win for you, and I agree with you that Cessna went about this in the wrong way, but it won’t be a win if your wing falls off.

    Speaking from personal experience as a structural engineer, airplane manufacturing companies (like Cessna) do care about their customers, and want to rectify problems when they come to light, before accidents occur, or there is loss of life. Having ADs issued against products made by your company is a stain on the reputation of your company, and is not a company’s first choice for solving problems. Generally speaking, when ADs are issued the manufacture is not thrilled about it. When a manufacturer does ask for an AD, but the FAA does not issue it, the manufacturer has a more heightened sense or awareness of the risks involved than does the FAA. And, yes, the FAA is sensitive to the various alphabet and model-specific support organizations that will have a cow when an onerous AD is issued against their beloved.

    There are two ways of looking at this. It could be that Cessna is trying to limit its tail of liability by undermining the resale value of one of its older products. Or, it could be that Cessna is very concerned about a legitimate design or manufacturing issue, and wants to ensure that the issue is taken seriously by the owners of these airplanes, and addressed in a way that will not be overlooked or dismissed. This first view ascribes greedy, self-serving motives to Cessna, who would purposely and needlessly inflict monetary damage on its own customers. The second view would be consistent with a company that values its customers, feels strongly about what actions are appropriate to protect the fleet, its customers, and flying public, but could not persuade the FAA to take up the cause against the lobby of the model support groups.

    Maybe the truth is in the middle – a combination of the two views – where an airplane needs to be put out to pasture for the good of its customers. I don’t know, and I don’t own a C-210. I’m just pointing out that winning the right to ignore the advice of the manufacturer’s maintenance recommendations may not be a win for everybody.

    • Evan, there’s no doubt in my mind that Cessna’s intentions were good here. And as I explained in my original post last Fall, I have absolutely no objection to the eddy-current spar inspections that Cessna proposed. They aren’t excessive, and if I owned a cantilever wing Cessna 210 I would voluntarily do the inspections that Cessna wants done.

      My problem with Cessna was strictly the procedure they employed in an attempt to make the inspections compulsory (i.e., required by regulation) without jumping through the normal hoops. If Cessna was permitted to get away with doing that, then it would set a precedent whereby any manufacturer could mandate anything they wanted without the normal protections mandated by the APA. The next manufacturer to do that might not have such pure motives and might be trying to mandate something totally unreasonable.

      It wound not surprise me if, in light of what just happened, Cessna once again asks for an AD and the FAA decides to go ahead with an NPRM. I would be happy with that outcome. It’s the right way to handle things like this. –Mike

      • Liberal in CA

        June 23, 2015 at 6:42 pm

        Mike I can’t speak to Cessna’s intentions, but I am less optimistic than you, and I am not convinced the inspection requirement is reasonable based on the evidence Cessna has provided. As you noted there hasn’t been a failure and the history Cessna provided with the AD request was obviously not compelling – and from experience we know the bar for convincing the FAA to issue an AD is not very high. The “hoops” as you call them that the FAA is required, by law, to follow in proposing and issuing an AD are there to protect the public and intended to provide transparency and public oversight. The FAA circumvents the process themselves with “emergency” ADs and various interpretation and policy statements that bypass the rule making process – and through the folklore they perpetuate in IA training material. There are numerous examples of ADs issued that are unjustified and some even that are counter to maintaining airworthiness as issued, sometimes even when the public comment and response process is followed (the value of this oversight depends on people paying attention and participating). This is the main flaw with the “consensus” process used for LSAs, the lack of public oversight and transparency.

  9. Vince Massimini

    June 29, 2015 at 7:45 pm

    Good article and action. Darn, I wish we could have done something like this with the Lycoming crankshaft AD!! (Which was done according to the APA, unfortunately.) Best, Vince

  10. Roberto Santamaria

    June 30, 2015 at 11:51 am

    Thank you for this Mike. This LOI will be very helpful down here in Chile.

Comments are closed.