In the last 5-6 years, we have heard the abbreviation AMS much more than we used to.
So what is this AMS?
Aerospace Materials Specifications (AMS) standards are published by The Aerospace Metals Engineering Committee (AMEC) , a subtask of the Society of Automotive Engineers ( SAE ) International , based in the United States . Under the AMEC committee, different subcommittees are assigned according to their areas of expertise. For example, metal-related standards are prepared by the AMS Metals Committee. These committees include high-level materials engineers from global OEM manufacturers, representatives from tier 1 suppliers, and government agency officials.
These committees meet at certain intervals (mostly 4 times a year) and the standard is published as a result of a detailed review process. Each publication has a revision interval of 5 years. If there is no situation that will have a significant technical impact on the products subject to the standard, no revision will be made before 5 years. In fact, due to the intensity of the committees, most of these documents exceed the 5-year revision period.
Revisions of AMS standards are indicated by letters, not numbers, like ASTM's. For example AMS 2750EIf you have an AMS standard, there are some terms you should pay attention to;
This term "ACTIVE" indicates that the standard will be in effect for the next 5 years. It has four separate subcategories. Issued, Revised, Reaffirmed, and Stabilized. Apart from these four expressions, there is also the term "CANCELLED", but it is not possible to see it in a printed document, you may come across this phrase on the AMS website.
I'm sharing an AMS letterhead below.
According to this letterhead, the standard was published in 2005, approved once in 2014 without any changes, and was last revised in 2018, receiving Annex A and entering into force. To prevent the revision from being overlooked, an (R) was placed right in front of its name.
Why is it needed?
Since the sector it addresses is aviation, space and defense companies, these are carefully scrutinized documents. Many main industrial aviation companies carry out their inspections through these documents.
If I had to compare AMSs in terms of content with other standards I have worked with (ISO, EN or TSE), I would have to point out that they are much more detailed and technical. They describe the process to be performed down to the smallest detail either within the standard or in the ASTM standard it is associated with.
Speaking of AMS standards, I would also like to mention ARPs, which I can call its siblings. Aerospace Recommended Practices explains the details of the application to be performed in these documents in a hands-on manner.
As a result, these specifications can be used as source documents even if no aviation work is carried out. I don't think I need to say that the conditions are really harsh.