Bill, That's all well and good. But my experience with waiching how the FAA does business with the airline industry since 1993 leads me to these conclusions--
1. The FAA is going to do what they are going to do. Yes, there is an agenda here and we aren't privvy to all the details. Express your outrage if you wish, but don't expect it to accomplish anything constructive. Better yet, express your outrage to your congressman or senator, or directly to the Administrator, because you are wasting your ink to include that in any response to the ACS. 2. Hoping this problem will go away or that the solution will be simple and easy is like burying your head in the sand. There will be an AD forthcoming. 3. Not cooperating or withholding information from the FAA is in nobody's best interest. The less information the FAA has to work with, the more severe their "fix" to the problem will be. I think we should provide them with as much information as possible to help them make the best decision. That does not guarantee that we will be able to live with the solution, but I guarantee it will be worse if they make a decision in a vacuum. 4. Cooperation is probably the best way to get information from the FAA regarding exactly what they are looking for. My airplane has holes drilled in the main spar cap to mount the seat pan. The seat pan is of original design but it's obviously a replacement with no documentation in the FAA 337 file. The previous owner found broken screws and stripped threads and enlarged some of these holes to drill out the broken screws and re-tapped them from #6 to #10. The A&P who did the annual and another AI who did the pre-buy were both aware of this and signed it off-- neither considered it an issue. Without knowing the specifics, it's hard to know if my airplane will be one of the ones affected, but I'm assuming it will. I'm hoping to get more information soon through the EOC that will help me determine if I need to be concerned or not. If I don't get some more information withing the next four to six weeks, I will be contacting the FAA and to explain what I've found and sending pictures. Getting into a pissing match over this will only hurt us in the long-run. The airlines have the money, lobbying power, and legal resources to do damage control when the FAA puts a heavy burden on them to comply. We don't, and I doubt I doubt Univair does. We're little fish to the Feds. Ultimately it will be their engineering department that makes the call based on data supplied from the field, and all the "what iffing" and armchair analysis from a bunch of owners is just wasted energy. JMO, YMMV, Dave --- In [email protected], William R. Bayne <ercog...@...> wrote: > > > Hi Ed, > > This "Airworthiness Concern Sheet", at present, merely indicates that > someone unnamed unilaterally initiated "safety recommendation" 09.087 > proposing revision of AD 2003-21-01 so as to require repetitive > inspection of the complete wing spar for "corrosion, damage and any > unauthorized maintenance actions performed on the wings of all Univair > Aircraft Models. It does not purport to duplicate the actual wording > or contents of "safety recommendation" 09.087, nor does that document > appear to be available on the FAA site by any link to AD 2003-21-01. > Searches using the words "safety reccomendation" do not lead to listing > of such purportedly pending documents. This, and the conspicuous lack > of specific information on the number, size location and proximity to > each other of the "unauthorized holes" seems consistent with an intent > to consciously discourage credible technical responses before the > stated deadline and thusly "run out the clock" on the required comment > period. > > It seems to suggest that if one or more "unauthorized holes" may, in > the abstract, reduce the original structural load carrying capability > of an Ercoupe wing in the slightest, that any and each such reduction > constitutes a genuine threat to the present and continuing > airworthiness of subject fleet. That is simply not true. It is also > preposterous to suggest that one or more "unauthorized holes" of a > given size and proximity adversely affect the load carrying capability > of an operational Ercoupe wing more than one or more "authorized" > (approved) holes of the same or larger size (except as specific > engineering analysis can show this to be the case). > > The FAA has only the obligation to assure that such "unauthorized > holes" do not reduce the load carrying capability of an Ercoupe wing to > something below required design requirements light aircraft in the CAR > 03 Normal category. They do not have the obligation, nor should they > be given the authority, to arbitrarily declare a spar with > "unauthorized holes" unairworthy. Such would do absolutely nothing in > terms of genuinely improving operational safety of the Ercoupe fleet. > It would impose such draconian financial burdens on affected owners as > would likely result in numerous perfectly safe and currently > operational aircraft being scrapped. It would make a mockery of any > illusion of meaningful cost-benefit analysis in the Airworthiness > Directive process. > > If the FAA is truly concerned about holes in the spar that may actually > reduce the aerodynamic load carrying capacity of a given operational > wing structure below applicable design requirements, then let it > actually state such concern and propose an empirical engineering > evaluation method consistent with such concern for our review and > comments prior to final consideration or adoption. > > It is interesting that this "Airworthiness Concern" is an "end run" > around the normal regulatory process, purporting to merely amend an > existing AD. Not so. The "unsafe condition" presented in AD > 2003-21-01 is "...to prevent wing damage caused by a corroded wing > outer panel structural component, which, if not detected and corrected, > could progress to the point of failure." Such "unsafe condition" of > suspected corrosion in the wing outer panels is of entirely different > origin, location and purpose than this new "Airworthiness Concern". > > It would authorize an open-ended repetitive "witch hunt" for "damage > and any unauthorized maintenance actions performed...". It would > address an entirely different "unsafe condition" located in an entirely > different section of the aircraft. This would be "...to prevent such > in-flight wing failure(s) in the fuselage center section of the wing > spar as might originate from one or more "unauthorized holes" therein." > I plan to specifically accuse the FAA of attempting to circumvent its > own process for the initiation of new ADs, and demand that said process > be complied with in full in this instance for the simple reason that a > single crash does not establish the existence of a fleetwide problem > requiring FAA action or "correction" in the field. > > But we also must encourage responses to this "Airworthiness Concern > Sheet". I have been working on a very comprehensive one for several > days. I will send it both by email and U.S.P.S. Certified Mail, Return > Receipt requested; and then post it to Tech. That makes it harder for > the FAA to "lose" or ignore comments (claim they did not get them). > Everyone is welcome reproduce any portion of it or incorporate any of > my thoughts expressed herein in their comments with the single > exception of the following: > > Should any of us wish to engage in engineering evaluation, i will share > a letter dated 10/12/49 from ERCO's Thomas M. Mountjoy, Assistant Chief > Engineer, addressed to the British Joint Services Mission in > Washington, D.C. At that time a 415-CD was being officially evaluated > in England. > > Airplane limit load factors > > CAR 04 1260 lb. +4.58 (- not available) > CAR 03 1400 lb. +3.50 -1.40 > > Limit wing load factors > > CAR 04 1260 lb. +4.64 -1.75 > CAR 03 1400 lb. +3.59 -1.32 > > Ultimate load factor = 1.5 x limit load factor > > And no, I'm not an engineer of any kind either ;<) > > Regards, > > William R. Bayne > .____|-(o)-|____. > (Copyright 2009) > > -- > > On Sep 20, 2009, at 08:43, Ed Burkhead wrote: > > > > One thought: It seems to me that holes in the upper spar cap would > > most likely be a problem when pulling negative g's, wouldn't they? > > Or, during extreme vibration (i.e. flutter)? I wouldn't think normal > > flying loads within the normal positive g limits would strain the > > upper spar cap. > > > > But, then, I'm not an engineer of any kind. > > > > Are there appropriate non-destructive diagnostic means to inspect for > > cracks in the spar cap? Dye penetrant? Portable x-ray? > > > > Do we have any aeronautical engineers here? > > > > Ed >
