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Possible Airworthiness Issue for 2001-05 DA40s

Posted: Mon Jan 08, 2018 9:35 pm
by blsewardjr
As I noted in another thread, the revised DA40-180 AMM Addendum is out -- http://support.diamond-air.at/fileadmin ... dendum.pdf

The addendum clearly states that Major Structural Inspections (MSIs) are part of Chapter 4 -- Airworthiness Limitations and are therefore required at 2000 hours or 12 years, whichever comes first, with a maximum tolerance of _+ 2.5% (about 3.5 months) for N-registered aircraft.
A Major Structural Inspection (MSI) is required: at 2000 hours since new or 12 years (that which comes first) and at 2000 hours intervals or 12 years (that which comes first) after the initial MSI. Maximum tolerance is ± 2.5% OR If MÄM 40-394 or MÄM 40-398 is installed: at 6000 hours since new and every 4000 hours intervals or 12 years, whichever comes first. Maximum tolerance is ± 2.5%


Heretofore, MSIs have been listed in Chapter 5, which is NOT mandatory for N-registered aircraft. I called Diamond Canada and spoke to the head customer representative, Will. In response to my inquiries Diamond had a meeting to discuss. With his permission, this is their position.

Diamond's position that is the following language in Chapter 4 means that even though MSIs are contained in Chapter 5, they are MANDATORY AS CHAPTER 4 Airworthiness limitations. Prior to the addendum, the relevant section of Chapter 4 stated:
(2) Life Time Limit / Structure Checks%
There is no structural life limit.%
Note: The DA 40 has been designed and tested under a 'damage tolerant structure'% philosophy. Therefore the structural inspections given in Chapter 05 cover all required structure checks.
See Chapter 4, page 5 in http://support.diamond-air.at/fileadmin ... mplete.pdf at page

Diamond's view is that the language in bold has already required MSIs as Chapter 4 airworthiness limitations and that the addendum only clarifies that. Diamond further believes that the extension to 6000 hours if "MÄM 40-394 or MÄM 40-398 is installed" does NOT change the fact that an MSI is required at 12 years, if that comes first. (Despite the fact that the sentence structure and wording used are completely different from that used for the 2000 hour limit.)

I would be interested in what you all think. Thanks. Bernie

Re: Possible Airworthiness Issue for 2001-05 DA40s

Posted: Tue Jan 09, 2018 2:47 am
by smoss
In reviewing the AMM, it appears the MSI items are really nothing special. Mostly inspecting inside various areas using a light and mirror, etc., via access holes. Unless I missed something in the checklist for "MSI", they are things that are probably done already, or easy to do anyways.

Re: Possible Airworthiness Issue for 2001-05 DA40s

Posted: Tue Jan 09, 2018 2:57 am
by blsewardjr
I agree but I believe it requires removal of the horizontal stabilizer to do so.

Re: Possible Airworthiness Issue for 2001-05 DA40s conclusion

Posted: Mon Jan 15, 2018 10:14 pm
by blsewardjr
For what it’s worth, my current mechanic discussed with his FAA contacts and the conclusion was that what currently governs US registered DA40s is the DA40-180 AMM rev 7, which places this inspection in Chapter 5.

Re: Possible Airworthiness Issue for 2001-05 DA40s

Posted: Thu Sep 13, 2018 9:50 pm
by linzhiming
Has anyone had any experience with how the MSI requirement is handled now?

I have looked at the FAA type certificate data sheet at http://rgl.faa.gov/Regulatory_and_Guida ... Rev_16.pdf, which records the transfer of the TC ownership from Austria to Canada, and states

"Instructions for Continued Airworthiness and Service Life Limited components is included in the Maintenance
Manual Document No. 6.02.01. Revisions to Airworthiness Limitations must be TCCA approved for the FAA."

On that basis, I would think that the addendum to the AMM with the Chapter 4 MSI airworthiness limitation at 12 years would apply to N-registered aircraft.

Has anyone done the MSI (scope is 2000h inspection + additional MSI work) and experience how much it would cost?

Wolfgang

Re: Possible Airworthiness Issue for 2001-05 DA40s

Posted: Fri Sep 14, 2018 5:17 pm
by Rick
My 2007 DA40 will turn over 2000 hours before my next annual in 3 months, so I guess I will find out what the "new" rules are then. I, too, am interested in the experience of others here who have done the 2000 MSI (or if not, why?) - how big a deal, how much $$$, etc.

Re: Possible Airworthiness Issue for 2001-05 DA40s

Posted: Sat Sep 15, 2018 1:52 pm
by smoss
Per this recently released FAA notification, changes to the airworthy limitations are NOT mandatory to do. Although it's a bit confusing, after reading it a few times, appears to say only the original airworthy requirements submitted with the original type design are mandatory, unless the new ones are also issued as an AD.

Re: Possible Airworthiness Issue for 2001-05 DA40s

Posted: Sat Sep 15, 2018 3:29 pm
by blsewardjr
Steve. Great find. That’s my read of this as well. Thanks. Bernie

Re: Possible Airworthiness Issue for 2001-05 DA40s

Posted: Sat Sep 15, 2018 5:26 pm
by linzhiming
Wow, that is really interesting and not what I would have expected.

If I understand the summary and the legal interpretation itself correctly, the option for compliance with an airworthiness limitation revised after the date shown on my airworthiness certificate rests with the Part 91 operator.

The other interesting aspect is that one technically would need to have the AMM revision applicable at the aircraft's date of initial airworthiness certification available for consultation. Where am I (and maintenance shops) going to find that??

On the other hand, this is presumably mitigated (please correct me if I read the FAA documents incorrectly) as the option for inclusion of a change rests with the Part 91 operator, i.e. I could elect to *not* follow more restrictive airworthiness limitations but elect to follow less restrictive airworthiness limitations. For instance, AmSafe extended the ICAW requirement for the replacement of the inflator assembies from 7 to 10 and then 12 years, which I have happily followed (and hence "elected to incorporate").

Airworthiness limitations aside, I am nonetheless considering having the MSI carried out (but at least I would not be legally bound to follow the exact 12 years + 3.6 months tolerance time period). Has anyone had it done recently and could report on the cost and effort of such an inspection?

Wolfgang

Re: Possible Airworthiness Issue for 2001-05 DA40s

Posted: Sat Sep 15, 2018 7:22 pm
by Steve
smoss wrote:Per this recently released FAA notification, changes to the airworthy limitations are NOT mandatory to do. Although it's a bit confusing, after reading it a few times, appears to say only the original airworthy requirements submitted with the original type design are mandatory, unless the new ones are also issued as an AD.
I received this by email from the FAA a few days ago, and that was my read as well. It appears that as a Part 91 operator, I do not have to comply with more restrictive airworthiness limitations issued after the original TC (e.g. MSI), but am permitted to apply less restrictive requirements which are issued after the TC (e.g. rudder cable replacement).

Hard to believe...