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Korean Opportunity

MARPA will present a workshop about PMA to Korean companies on August 24-25.  This workshop is being put on in partnership with the Korean Government (KOTRA and MOLIT).

We will be discussing issues that affect Korean-US business relationships and strategies for increased Korean-US trade.  MARPA members will be networking with existing and potential Korean business partners.

Registered attendees include personnel from airlines Asiana Airlines and Korean Air Lines (KAL).  This could be a great opportunity to network with some Korean customers and business partners.

We should be able to secure complimentary registration for any MARPA member who wants to attend.  If you have personnel in the Republic of Korea or elsewhere in northern Asia, then you should certainly have them on site for this meeting.

If you have personnel that you would like to register for the workshop, please let MARPA know ASAP as time is running short.

Yes, You CAN Sell FAA-PMA Parts into China!

Yes, China accepts FAA-PMA parts.

The United States and China signed a Bilateral Airworthiness Agreement (BAA) in 1991.  That agreement recognized that each authority (FAA and CAAC) had a system for production and airworthiness approval of civil aeronautical products, and that each system was sufficiently equivalent to the other to permit the authorities to accept certain approval decisions of the other.

The BAA is implemented through a Schedule of Implementation Procedures.  This schedule explains how international aerospace transactions will work.  It is meant to facilitate certain transactions and relationships.
The schedule covers, inter alia, Chinese acceptance of FAA Export Certificates of Airworthiness appliances, parts, and materials for which the FAA is the exporting authority.  The schedule explains that China will accept US export certificates of airworthiness for parts and materials when the FAA certifies that each article:

(a) Conforms to approved design data;
(b) Is properly marked; and
(c) Meets the special requirements of the importing country.

This is typically done through the issue of an FAA 8130-3 tag.

The special import requirements of China must be formally presented to the United States, and then the United States publishes those special import requirements in Advisory Circular (AC) 21-2.  The Chinese special import requirements apply to airframes, engines, propellers, and TSOA articles, but the only special import requirement that applies to FAA-PMA parts is that the part must be accompanied by an 8130-3 tag.  Since the 8130-3 tag is the medium for communicating the compliance, the 8130-3 for a FAA-PMA part can be safely annotated as meeting the special import requirements of China.

The Chinese have clarified in several places that they really mean it when they say that they are accepting PMA parts.

In order to ensure that there is no confusion, appendix D of the Schedule of Implementation Procedures specifies that the term ‘part’ means replacement and modification parts manufactured under any FAA production approval.  The appendix goes on to say that this includes replacement and modification parts manufactured by an FAA-PMA holder!

Some additional provisions are listed in the Schedule of Implementation Procedures , but none of them actually impose any additional obligations on someone who exports a PMA part to China, so long as that part already complies with US regulatory standards.

  • Critical components must have a part number and a serial number (this is already required under FAA Part 45 for FAA-PMA parts); and
  • All PMA parts must be marked with the part number and the manufacturer’s name or trademark (this is also required of all PMA parts under FAA Part 45 marking requirements).

China has also published their own advisory circular on the acceptance of FAA-PMA parts.  The advisory circular clarifies that FAA-PMA parts are acceptable for use on Chinese aircraft and reiterates that the parts should marked according to the requirements of FAA Part 45.

MARPA Efforts to Increase PMA Sales to Southeast Asia and China

MARPA is organizing the first-ever PMA Trade Mission to Singapore and China (Hong Kong, Guangzhou, Shanghai and Beijing) for November 3-13, 2015.

The purpose of this trade mission is to introduce air carriers and MROs in Southeast Asia and China to the concept of PMA, and to the significant advantages that they can recognize by doing business with PMA manufacturers from the United States.  We hope that this will help increase PMA sales into these regions.

The mission will begin for MARPA at MRO Asia in Singapore, November 3 through 5.  We are planning to set up a few pre-scheduled meetings as well as allowing members to interact with the MRO attendees.  After MRO, we will fly to Hong Kong to meet with air carriers on Friday.  We plan to transfer to Guangzhou over the weekend in order to meet with Gameco and China Southern on Monday.   Then we will spend Tuesday-Wednesday in Shanghai and Thursday-Friday in Beijing meeting with air carrier and MRO sales targets.

If you aren’t yet selling into Asia, then this is a wonderful way to start meeting potential customers.  If you already have business in Singapore, China and Hong Kong, then you won’t want to miss this exceptional opportunity to renew acquaintances and build more business.

Tails at Beijing Airport

Tails at Beijing Airport

MARPA has been planning this 2015 trade mission since late 2014, and we’ve enjoyed incredible support from our US government contacts.  This trade mission is undertaken in partnership with the US Department of Commerce, and we are being assisted by the International Trade Administration and the Commercial Foreign Service officers in the embassies and consulate offices.  This is a valuable membership benefit that is available to help MARPA members increase their export business so make sure you take advantage of it!

If you are interested in participating or want more information, then please contact the Association.  We’d love to hear from you.

We hope to soon be able to offer a specific itinerary and price for the mission.  Once this is announced, we will take firm commitments from members on a first-come-first-served basis until the program is full.

Wondering if you can sell PMA parts into China?  Tomorrow we will start addressing the legal standards for PMA acceptance in China!

MARPA Air Carrier Committee Seeks Clarification on post-AD PMA Parts

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 katt@washingtonaviation.com.  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.

Mike Rennick Talks PMA Reliability at Delta Air Lines

Those who attended MARPA’s inaugural European conference last month in Istanbul were treated to an excellent presentation by Delta Air Lines Manager of Component Engineering and MARPA Air Carrier Committee Chairman Mike Rennick on the impressive reliability benefits of PMA parts in Delta’s fleet.

As many know, Delta operates a very diverse fleet of aircraft, which are on average older aircraft than many other carriers’ fleets.  Yet Delta also operates one of the most reliable mainline fleets in the world.  In 2014, Delta had an impressive 169 maintenance cancellation free days; a metric that has improved each of the last three years.  Mr. Rennick pointed out that one of the important contributing factors to this success was the widespread use of PMA parts.

MARPA and its members frequently tout the many benefits PMA provide to operators.  Operators are generally aware of the lower prices offered by PMA parts.  They are also aware that PMA parts may be their only option, or one of very few options, for replacement parts for legacy aircraft. However, operators may not be aware of the significant reliability benefits that PMA parts also provide.

Mr. Rennick explained that in order to maintain its fleet to the level it requires Delta wants options.  Service experience has demonstrated that PMA parts match, and in some cases exceed, the performance of OEM parts.  Based on this experience Delta has found PMA parts to be acceptable for use throughout the aircraft, components, and engines.

Mr. Rennick’s presentation included exciting metrics showing an upward trend in Mean Time Between Unscheduled Removals (MTBUR) and Mean Time Between Failures (MTBF) on certain applications in which Delta had utilized a PMA solution.  Metrics like these indicate the great value proposition that PMA’s can offer air carriers; not only from a purchase price standpoint, but importantly, from a reliability standpoint.  These metrics, along with shortened lead times, are part of the greater holistic value proposition offered by PMA parts and something we should remember to emphasize when talking to potential customers.

Mr. Rennick also stated that because of Delta’s close cooperation with its vendors it is able to address issues more quickly than might otherwise be possible.

Delta’s comfort level born of experience with PMA parts has led to the carrier using PMAs in even very critical applications, including engine gas path and rotating parts, life limited parts, and power generation.

The emphasis on the reliability of PMA parts is one that we, as an industry, should be sure to promote to our customers.  Cost savings means more than just lower prices (an obvious benefit of PMA!)  Keeping aircraft safely and reliably operating without unscheduled removals and increasing time between failures generates cost savings for operators by allowing them to get planes turned quickly and keeping their passengers happy.  MARPA always makes it a point to emphasize the reliability benefits of PMA wherever we go.

If you were unable to join us in Istanbul you will still have a chance to see this great presentation on the reliability benefits of PMA parts.  We anticipate Mr. Rennick giving a similar presentation at the 2015 MARPA Annual Conference.  This will be a great opportunity for PMA manufacturers to hear directly from Delta on the air carrier’s take on PMA parts, and an excellent opportunity for operators to see how one carrier is making PMA parts an important element of their maintenance program success. Register today to take advantage of Early Bird rates!

New Guidance: Casting and Proof of Structure

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).

  • Casting Factors, AC 25.621-1: This AC provides guidance for meeting the requirements of 14 C.F.R. 25.621.
    • This regulation imposes limits and restrictions on casting, and also requires a design approval applicant/holder to have control over the operations of a vendor casting facility.
    • The intention of both the regulation and the AC is to drive greater levels of consistency into casting (or to mitigate inconsistencies).
    • Discusses a means of qualifying a casting process

 

  • Proof of Structure, AC 25.307-1: This AC provides guidance for meeting the requirements of 14 C.F.R. 25.307.
    • This regulation is for the demonstration of compliance for each critical loading condition.
    • The AC provides a list of factors that should be considered in deciding the need for and the extent of testing, including the load levels to be achieved.
    • The AC states that there are four certification approaches to choose from (and provides guidance on each one):
      • Analysis supported by new strength testing of the structure to limit and ultimate load.
      • Analysis validated by previous test evidence and supported with additional limited testing.
      • Analysis supported by previous test evidence.
      • Test only.

We would be interested in hearing from any MARPA member who is affected by one of these new advisory circulars.

FAA Issues Statistical Analysis Guidance – Are You Testing Enough Parts?

The FAA has issued a new advisory circular for statistical analysis.  This AC only applies to engine and APU parts.

The new advisory circular uses statistical analysis to arrive at correct sample sizes.  This sample size formula is introduced for persons who are trying to correlate two populations of parts.  MARPA had pointed out to the FAA that typically a PMA applicant does not correlate two different populations of parts – instead they derive the reasonable tolerances on one population of parts, and then design and produce within those tolerances.  The FAA would like PMA applicants to arrive at their appropriate sample size, test the parts being reverse-engineered, and then produce an equivalent number of pre-PMA parts to test for the same properties (and then correlate the two populations).  This is contrary to current FAA regulatory guidance, which requires the design to be approved and the  requires the production quality system to ensure that parts are all produced within the approved design parameters.  In essence, ACO engineers will now take control of the quality assurance system through the design process.

One of the problems with the AC is that it relied on statistical analysis for clinical trial sample size as the basis for assessing statistical analysis of reverse-engineering sample size.  Clinical trials for pharmaceuticals typically rely on populations of hundreds or even thousands of people.  Trying to test hundreds or thousands of parts in order to reverse-engineer them is simply not realistic.  Furthermore, the degree of part-to-part difference under modern quality assurance systems does not support such large sample sizes.
For those cases where the equations in the advisory circular give a lower number for the appropriate sample size, the FAA has also established minimum sample sizes.  The AC sets some minimum limits for the number of parts that must be tested in order to derive certain values (remember that you need that number of PC parts and also that number of reverse-engineered parts to meet the AC’s requirements):

Minimum Number of Parts to be Sampled

  • For basic material properties that are more dependent on alloy constituency than on part manufacture process – 10 approved parts from three separate lots with at least three parts per lot
  • For properties affected by how the material is processed during part manufacture such as high-cycle fatigue, low-cycle fatigue, creep, tensile strength, crack growth, etc. – 30 approved parts
  • For fatigue testing – at least 25 tested parts that are run until they crack
  • For parts exhibiting complex geometry or complex manufacturing variables, additional specimens may be required
  • For parts considered to have a high degree of criticality, greater sample sizes may be required

No statistical basis is offered for these minimum sample sizes.

The new advisory circular provides guidance for statistical analysis of sample-size despite the fact that no regulation actually requires such a broad-based sample.  The advisory circular appears to potentially change the regulations by increasing the burden on applicants.  To the extent that this is true, it is inappropriate.

Our concern is that despite warnings that this is non-mandatory guidance, this guidance may be used as if it were a regulation, with offices refusing to accept PMA applications that are otherwise valid, but that failed to use this AC as a basis for identifying sample size.

If you find that this AC effectively changes the application obligations imposed on you as a PMA applicant, STC applicant, or other FAA-approval applicant, then please contact MARPA so we can raise this concern with the appropriate personnel at the FAA.

AC 33-10 is known by its full title: Statistical Analysis Considerations for Comparative Test and Analysis Based Compliance Findings for Turbine Engine and Auxiliary Power Unit Replacement, Redesign and Repaired Parts.

Inappropriate Restrictions on the Use and Availability of ICAs

Some of you may be wondering where to find the FAA’s policy memo on design approval holder restrictions on ICA availability.  Older MARPA links to the original position of that guidance are no longer valid because it has been moved.  But it is still available if you know where to look!

Many MARPA members look for this policy memo because it clarifies that anti-competitive language in ICAs (restricting use of PMAs or third party repairs) is unacceptable to the FAA:

While not exhaustive, the FAA finds the following practices of using restrictive language in the ICA or through restrictive access or use agreements unacceptable under the provisions of 14 CFR §21.50(b) and related ICA airworthiness requirements:

1) Requiring the owner/operator to only install DAH-produced or authorized replacement parts, articles, appliances, or materials.
2) Requiring that alterations or repairs must be provided or otherwise authorized by the DAH.
3) Requiring the use of only maintenance providers or other persons authorized by the DAH to implement the ICA.
4) Establishing, or attempting to establish, any restriction on the owner/operator to disclose or provide the ICA to persons authorized by the FAA to implement the ICA.

The guidance has found a permanent home in the FAA Regulatory and Guidance Library.  A copy of that guidance is also available on the MARPA website.

MARPA and FAA Talk Policy

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 Files Comments on FAA Geometry AC

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:

    •  Possible confusion over availability of existing industry guidance;
    •  Apparent inconsistency with existing FAA guidance;
    •  Inaccurate implications that product testing is the only method available to collect data for lifing methods of life limited parts; and
    •  Issues regarding the specific practice of part selection for selective assembly components.

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.

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