The MARPA Air Carrier Committee, led by Michael Rennick, Delta Air Lines Component Engineering Manager, is hard at work supporting PMA users and MARPA members. In June, members of the MARPA Air Carrier Committee, including Air Wisconsin, American Airlines, Republic Airways, US Airways, Air Canada, and Delta Air Lines, submitted to the FAA a letter seeking clarification on the issue of PMA parts that are alternates to post modification Airworthiness Directive (AD) related parts.
This clarification is necessary because confusion has sometimes arisen between operators and local regulators over the need for an Alternative Method of Compliance (AMoC) for post-modification AD-related PMA parts. It is the position of the MARPA Air Carrier Committee that if the PMA is an alternate to an OEM part contained in a post-AD configuration, no such AMoC is required.
When a PMA is issued for a replacement part for a post-modification AD-related OEM part, it is uncommon for the PMA applicant to request an AMoC to the AD, or for the FAA to note the AD on the PMA approval. This makes some sense because a post-AD PMA part is inherently an alternative method of compliance without being described as one. However, an issue arises because many ADs call out only the modified OEM part as a means of compliance. Because ADs are technically regulations under Part 39, alternate approvals such as PMAs might not satisfy the regulatory requirement and so an AMoC may be required.
It would be beneficial to both operators and PMA manufacturers to see this change.
The OEM part is the source of the condition giving rise to the AD. The post-modification part must resolve the condition in order to satisfy the AD. During the PMA approval process for the same part, the AD is also taken into consideration.. In order to receive PMA approval, the subject PMA part must resolve the condition resulting in the AD, just as the post-modification OEM part does. There should be no need to call out an AMoC for the PMA part related to the AD; the underlying condition that necessitated the AD has changed because the approved PMA part has replaced the post-AD OEM part. The PMA should be a valid terminating action for the AD.
There are limited circumstances in which this reasoning may not apply, but these limited circumstances are not the subject upon which the Air Carrier Committee seeks clarification. For instance an AMoC may be necessary in a scenario in which an AD applies to a higher level component or assembly. In this scenario the PMA replacement for the OEM part may not address the AD for the higher assembly because it is a replacement at the piece-part level, and thus an AMoC may be necessary for the higher assembly.
Generally, however, an AMoC should be inherent in an approved PMA part and therefore unnecessary as a separate approval. This is the policy clarification that the Air Carrier Committee seeks in the form of a formal FAA communication. If an approved PMA part is a replacement for a post-AD OEM part, the FAA’s policy should clearly state that the approved PMA is a terminating action for the AD and that no additional approval or discrete AMoC is required. In the alternative, an AMoC could automatically issue for each post-AD PMA to show compliance.
MARPA greatly appreciates the Air Carrier Committee’s work on this project. MARPA will be working with the FAA and the Committee to determine whether future ADs will list an approved PMA as a valid terminating action, or whether an automatic AMoC should automatically issue with a PMA to show compliance to the AD, or some other solution is desired. We will keep our members apprised of these developments.
If you are a MARPA member air carrier and want to get involved with the Air Carrier Committee, please email Katt Brigham at firstname.lastname@example.org. If you are not yet a MARPA member but would like to get involved, visit our membership application page. MARPA membership is free for air carriers!
Edited to clarify that ADs are regulations and identify possible solutions to the issue raised in the Air Carrier Committee’s letter.
Do you want to serve on a FAA working group that will help the FAA shape regulations affecting safety? Do you have expertise in composite and other nonmetallic airframe materials? Can you add to a discussion about airframe crashworthiness?
The FAA has asked the Aviation Rulemaking Advisory Committee (ARAC) to provide recommendations regarding airframe-level crashworthiness and ditching standards that would be incorporated into the FAA’s regulations. TYhe group would also prepare advisory materials.
During the development of current airworthiness standards and regulatory guidance, the FAA assumed that airframe structure for transport airplanes would be constructed predominantly of metal, using skin-stringer-frame architecture. Therefore, current regulatory requirements either do not address all of the issues associated with nonmetallic materials, or have criteria that are based on experience with traditionally-configured large metallic airplanes.
With respect to crashworthiness, there is no airframe-level standard for crashworthiness. Many of the factors that influence airframe performance under crash conditions on terrain also influence airframe performance under ditching conditions. Past studies and investigations have included recommendations for review of certain regulatory requirements and guidance material to identify opportunities for improving survivability during a ditching event; consideration of these recommendations is included in this tasking.
You can find a full discussion of the working group’s task, online.
If you wish to become a member of the Transport Airplane Crashworthiness and Ditching Working Group, you can express that desire by contacting:
Federal Aviation Administration
1601 Lind Avenue SW.
Renton, WA 98055,
phone number 425-227-2145
facsimile number 425-227-1232
Please describe your interest in the task and state the expertise you would bring to the working group. The FAA must receive all requests by July 6, 2015. The ARAC and the FAA will review the requests and advise you whether or not your request is approved. For MARPA members, if you would like MARPA’s endorsement for such a position, please contact us before the deadline.
We previously wrote in this space about a new Draft Policy Statement issued by the FAA concerning the vibration surveys and engine surveys required under section 33.83 of the Federal Aviation Regulations. The draft guidance attempts to more narrowly address the FAA’s concerns about full engine test for type certificate applicants.
MARPA plans to provide comments on this Draft Policy Statement to the FAA and has sent a draft of our comments to the MARPA Technical Committee for review. If any of our members wish to review our draft comments to provide their feedback we would love to hear from you. Please email Ryan Aggergaard at email@example.com if there are particular issues in the draft statement you believe should be addressed so that we can incorporate our members’ concerns.
MARPA also encourages our members to file their own comments on the Draft Policy Statement. Comments are due to the FAA by November 21, 2014. Comments should be emailed to Dorina Mihail at firstname.lastname@example.org. Comments can also be mailed to her at:
Federal Aviation Administration
Engine and Propeller Directorate
Standards Staff, ANW-111
12 New England Executive Park
Burlington, MA 01803
MARPA looks forward to your comments.
The FAA has released two new advisory circulars that may affect the PMA community. Both advisory circulars are issued by the Transport Aircraft Directorate and apply to Part 25 aircraft (and parts thereof).
We would be interested in hearing from any MARPA member who is affected by one of these new advisory circulars.
Do your export 8130-3 tags have the right language on them? If they don’t then you run the risk that they may be rejected in Europe.
The Bilateral Aviation Safety Agreement (BASA) between the United States and the European Union specifies that the documentation that accompanies a PMA part bound for the European Union must include specific language in order to be acceptable to the European Union’s airworthiness authority, EASA.
The BASA Technical Implementation Procedures (TIP) direct that PMA parts being exported from the United States to the European Union bear appropriate language in block 12 (the remarks block) of the export 8130-3 tag. In order to meet this requirement properly, the export 8130-3 tag must identify the part as falling into one of these three categories (by using the authorized language):
1. For a PMA part which is not a critical component, the remarks block of the 8130-3 should state:
“This PMA part is not a critical component.”
But if the PMA part is a critical component, then there are two options for the language in the remarks block.
2. In the first option for critical components, if the PMA holder also holds an EASA STC design approval which incorporates the PMA part into an EASA certified or validated product, then the language should say:
“Produced by the holder of the EASA STC number [INSERT THE FULL REFERENCE OF THE EASA STC INCORPORATING THE PMA].”
3. In the second option, if the PMA holder holds a licensing agreement from the TC or STC holder (giving the PMA holder the rights to use the TC/STC design for the PMA parts), then the following statement should be written in the remarks block:
“Produced under licensing agreement from the holder of [INSERT TC or STC NUMBER].”
These options 2 and 3 are the only two options for exporting FAA-PMA critical components from the US to the EU.
The PMA “criticality statement” is something that is requested under the technical implementation procedures (TIPs) that accompany the US-EU bilateral aviation safety agreement (BASA).
Under the US-EU TIP, a “Critical Component” is defined as:
“a part identified as critical by the design approval holder during the product type validation process, or otherwise by the exporting authority. Typically, such components include parts for which a replacement time, inspection interval, or related procedure is specified in the Airworthiness Limitations section or certification maintenance requirements of the manufacturer’s maintenance manual or Instructions for Continued Airworthiness.”
The determination of whether a PMA part is critical is made by the design approval holder (the FAA-PMA holder) and confirmed as part of the FAA approval. Section 4.4(c) of Order 8130.21H states that “The determination of a PMA article’s criticality, as required to be entered in Block 12 when exported, can only be determined by the actual design approval holder (that is, the FAA-PMA holder).” This is important language because certain parties (foreign governments and competitors) have attempted to gainsay the FAA-approved “critical part” decisions of the FAA-PMA holders.
we have heard of DARs who thought that this language meant that only the PMA holder could obtain the export 8130-3 tag. This is not so. This language is not meant to prevent a designee issuing an export 8130-3 tag from making a PMA “criticality statement” on the 8130-3 tag that is consistent with the determination of the design approval holder. Thus, any designee issuing an export 8130-3 tag for any FAA-PMA part may rely on the (PMA) design approval holder’s determination as to whether the PMA part is a critical component.
This critical parts language generally does not appear to apply to most bilateral airworthiness agreements – it is a special nuance of the US-EU Agreement. Adding the “criticality” language does not hurt the 8130-3 tag (and may be useful if the end-user is not yet known), but the criticality language generally remains unnecessary unless the part is destined for Europe.
The FAA has released Notice 8110.116, which stresses the importance of writing clear notes in the Type Certificate Data Sheet (TCDS), and of ensuring that those notes are consistent with FAA policy. This new guidance can be very valuable to everyone in the industry. The value to TC applicants and holders (who create draft TCDS for FAA adoption) is obvious, but less obvious are the subtle and not-so-subtle admonitions against using the TCDS for anti-competitive effect.
One valuable element of this guidance is that it stresses certain things that should not appear in the TCDS. For example, in paragraph 6(a)(6), the guidance advises against language that limits work to a scope narrower than permitted by the regulations:
(6) Do not include requirement that is non-regulatory in the notes. For example: “This aircraft shall be maintained in accordance with the BHT-427 Maintenance manual.” This note implies that BHT-427 is the only source for maintaining the aircraft, and conflicts with 14 CFR 43.13(a) which states “Each person performing maintenance . . . shall use methods . . . or other methods acceptable to the administrator.”
This admonition is consistent with FAA guidance that has prohibited language limiting operators options in seeking repairs. E.g. PS-AIR-21.50-01: Type Design Approval Holder Inappropriate Restrictions on the Use and Availability of Instructions for Continued Airworthiness (March 23, 2012). In the past, there have been problems with manufacturer’s guidance that seeks to limit operators’ repair options, which in turn has had an adverse effect on independent repair stations who are qualified by the FAA to perform the same repairs. Other language in the guidance highlights the prohibition against anti-competitive statements by stating:
Avoid language promoting a TC holder or their suppliers as the sole source for maintenance or overhaul.
It is contrary to 14 CFR parts 43 and 21 to include a note that all repairs or modification schemes must be approved by the TC holder prior to FAA approval.
In a similar vein, the guidance also forbids use of notes that could be interpreted as statements of FAA General Policy. The obvious reason for this is because the TCDS should not be used as a vehicle for establishing FAA policy. The example that is given is useful in its own right, because this is clearly not a statement of FAA policy, despite the fact that some government prosecutors have tried to promote similar policies:
(8) Avoid notes that can be interpreted as FAA general policy. For example: “Reuse of parts and assemblies that have been involved in an accident is not permitted unless approved by FAA Engineering.”
In subsection 6(a)(10), the FAA advises against the use of brand names, but in subsection (11), the FAA requires that when a specific brand name is used, then the note must also advise of the possibility of using FAA-approved alternatives:
(11) If a specific brand name material needs to be listed, then you must state that an equivalent material is also may be approved. For example: “SOHIO BIOBOR JF biocide additive is approved for use in fuel at a concentration not exceeding 270 PPM. Use of other, equivalent material, may be approved by the FAA.”
Aviation is a competitive industry, but some companies have attempted to use FAA-approved and FAA-acceptable documents as levers to inhibit competition. The FAA has repeatedly asserted that its job is safety – not competition – and that it will not allow its approvals to be used as independent inhibitors of competition where no safety interest is served. While the main purpose of this new guidance is to standardize the layout of TCDSs, it also includes important admonitions that should help prevent anti-competitive behavior.
MARPA had a very good meeting today with Mark Bouyer and Ann Azevedo of the FAA’s Engine and Propeller Directorate (EPD).
The focus of the meeting was status on EPD policy that may affect PMA manufacturers.
Azevedo explained that she has responded to the comments on the Statistics Advisory Circular (AC), and hopes to have the final draft of that guidance available to the public by September. The Statistics AC is meant to address FAA concerns that have been recognized in practice, such as misusing statistical methods to show equivalence, and underestimating the appropriate sample sizes.
Bouyer expects the Materials AC to go out for public comment this month. The Materials AC will identify the essential data that is necessary when a PMA applicant is trying to replace the material used in the type design. MARPA members should watch for this one, and be prepared to offer their comments.
The FAA had published the Geometry AC for comment. This AC is meant to enhance awareness of how reverse engineering can introduce dimensional differences in replacement parts. MARPA Board members have expressed that the draft of this proposed guidance appeared to be very helpful to the industy.
The Burner Rig AC, which was also previously out for comment, is expected to be issued by September. It is expected to provide a method for establishing functional equivalence for certain degradation modes in parts such as oxidation, hot corrosion, erosion, etc. The AC is expected to identify existing technology as a means of compliance.
Finally, the FAA is internally reviewing AC 33.8 with a plan to update and clarify the AC. The updates are intended to make the AC easier to use.
The FAA has been very active and diligent in preparing guidance. In the immediate future (before the Conference), MARPA members should expect to see the release version of the Statistics AC and the Burner Rig AC, and they should expect to see the Materials AC go out for comment.
MARPA recently filed comments on the FAA Engine and Propeller Directorate’s draft Advisory Circular 33-Geometry, discussing geometry and dimensional considerations for comparative test and analysis for turbine engine and APU replacement parts. In a previous blog post we observed that AC identified a number dimensional and geometric factors that the FAA expects to be assessed in ensuring the integrity of dimensional characteristics for the purposes of showing similarity.
We requested feedback from our members describing to what extent the FAA’s expectations were reasonable and practicable, and identifying any issues with the proposed guidance on which MARPA should comment. We received several very helpful responses from our members that helped us shape our comments to the proposed AC. Among the issues members identified were:
Feedback from our members is both helpful and valuable to our comments, as it helps us to identify issues that directly affect members’ businesses, and helps us to better focus our resources on those matters that are important to the PMA community. The result is more detailed and on-point responses to the FAA to better help shape the guidance material that will ultimately be issued.
We greatly appreciate the feedback we received from our members on this Advisory Circular, and we hope that our members will continue to answers our requests for responses as additional guidance and rulemaking documents are issued. Together we can work with the FAA to develop the best possible guidance for our industry.
The FAA is currently seeking comments on its Draft Advisory Circular Engine Overtorque Test, Calibration Test, Endurance Test, and Teardown Inspection for Turbine Engine Certification (§§ 33.84, 33.85, 33.87, 33.93).
As the title suggests, the AC offers guidance on compliance with the engine overtorque, calibration, and endurance tests, and teardown inspection called out in Part 33 of the Federal Aviation Regulations. Although the guidance is directed at engine manufacturers, foreign regulatory authorities, applicants for engine type design approval, and FAA designees, it also notes that parts manufacturer approvals “may require running certain endurance testing for compliance with § 33.87″ and refers to AC 33.87-2 for guidance on showing compliance by comparative test methods.
MARPA would like to know to what extent members anticipate this AC might effect them, and whether we should submit comments. If you plan on submitting comments, or have already done so, we would would like your feedback so that we can incorporate member concerns into our comments.
Comments on the Draft AC are due next week, so if you have feedback for us please submit them to email@example.com soon!
Today, the FAA announced the issue of AC 21.3o3-4. The title of this AC will be “Application for Parts Manufacturer Approval Via Tests and Computations or Identicality.”
As of this time, the AC is not yet available to the public. When it is available to the public, it is expected to be posted online at this location:
Note: the issue date published on the FAA’s website is March 21, 2014; however the AC is not yet available through the FAA’s online advisory circulars, nor through the Regulatory and Guidance Library (RGL). The note on the FAA’s website states “This document‘s content is not currently available.”