Guide to ASTM Aircraft Certification Standards

A Guide to ASTM Aircraft Certification Standards

Introduction to ASTM Aircraft Certification Standards

In 14 CFR Part 23 Amendment 23-64, the Federal Aviation Administration (FAA) decided to rewrite the original 14 CFR Part 23 airworthiness standards for normal, utility, acrobatic, and commuter category airplanes (before Amendment 23-64) (if the previous link stops working, try to use this link to access historical Federal Aviation Regulations). For a general background that led to this development and the some of the ideas behind it, see for instance this AOPA article on understanding the Part 23 rewrite. The new version of 14 CFR Part 23 after Amendment 23-64 is kept on purpose somewhat broad and vague, conveying general performance-based criteria, and leaving the explicit details how to demonstrate compliance to a voluntary consensus standard of the industry, specified in the so called ASTM standards.

In addition, the FAA has published, which ASTM aircraft certification standards it considers to be an accepted means of compliance for the individual new paragraphs in 14 CFR Part 23, and what kind of modifications the FAA makes to these ASTM standards to satisfy Part 23 (since the FAA has no direct control over the content of the ASTM standards themselves). These FAA publications include:

The ASTM aircraft certification standards are not the only possible means of compliance for the new Part 23 regulations. However, for many practical purposes, this whole Part 23 rewrite has—aside from a few changes—led to the details of Part 23 simply having been moved into the ASTM standards, which are managed by ASTM International and not a U.S. government agency.

This seemingly innocuous change has a considerable practical ramification, because ASTM International does not provide access to its standards for free. You have to pay.

Accessibility Issue of ASTM Standards for Aircraft Certification

The information formerly contained in 14 CFR Part 23—which was available from the U.S. government for free before Amendment 23-64—is now scattered in over a dozen individual ASTM consensus standards (some of which we list below). Each of these ASTM standards documents costs between $61 and $119 (at the time of writing) to purchase from ASTM International. If you were to buy the whole set, it would cost you over $1000.

At first, it may seem to you by looking at the FAA accepted means of compliance list and side-by-side view of 14 CFR Part 23 regulations and ASTM standards (Table 2) that you may only need to purchase one ASTM standard, ASTM F3264. But the ASTM F3264 document is merely an index, with each section just telling you in which other ASTM consensus standards you will find the actual information for that section (the “subsections” of F3264 in the above Table 2 are actually separate documents to be purchased).

The ASTM online training courses are in a similar price category. For instance, this 4-hour online eCourse on ASTM Standards for Light Sport Aircraft costs $1150.

This ASTM paywall means that essentially—unless you work for an organization that has an ASTM subscription and provides you with unlimited free access to whichever ASTM standards you need—you have no practical way of accessing the information reasonably anymore, which used to be in 14 CFR Part 23 before Amendment 23-64. Of course, you can look up the old, historical 14 CFR Part 23 on the FAA website, but this information will become increasingly outdated and does not apply to newly certificated aircraft types.

Access to ASTM Standards for Aircraft Certification

We have mentioned elsewhere, how crucially important it is—not only for test pilots and flight test engineers, but also for operational pilots and flight instructors—to be familiar with the certification regulations of aircraft and what these aircraft have been designed for, especially for safety reasons. Stall and spin training, as well as upset prevention and recovery training (UPRT) in general, are prime examples.

Light sport aircraft (LSA) are certificated under ASTM F2245, not Part 23. Do they offer the same inadvertent 1-turn spin protection as Part 23 certificated, single-engine normal category airplanes? Well, you will not know, unless you read ASTM F2245. And for new Part 23 airplanes this information is in ASTM F3180 now and has been reworked to involve a departure characteristics score.

Unfortunately, we cannot send you the PDFs of the ASTM standards, because it is copyrighted material and intellectual property of ASTM International. Sharing it with you unabridged would constitute a copyright violation. However, we can teach selected sections from these standards as needed, under fair academic use. More specifically, if you have any questions about individual paragraphs in the ASTM standards, or questions about a 14 CFR Part 23 paragraph and are wondering where in the ASTM standards you can find more, we will be happy to help you, because we understand your plight. Please contact us, if you have any questions and would like to seek our assistance.

We volunteer our time and provide this information and education for free for the benefit of pilots and for the safety of the aviation community. We hold weekly office hours (on one weekday evening) by appointment to answer any of our clients’ questions (not just those relating to ASTM standards).

Any information provided by us is merely for general educational and training purposes only, and shall not be used for any actual aircraft design, aircraft certification, flight test, flight operation, or any other professional or private work, which these ASTM standards refer or apply to. Especially for professional work in aerospace and flight test engineering, you must purchase the actual ASTM standards for aircraft certification you require and read the original documents yourself (typically your organization where you work will provide access to these documents, if you need them).

Below please find a small selection of ASTM aircraft certification standards of particular interest to test pilots, flight test engineers, operational pilots, and flight instructors. Keep in mind that there are many more ASTM standards for aircraft certification than those listed.

List of Selected ASTM Aircraft Certification Standards

The links in the list of ASTM aircraft certification standards below point at the most current version of each ASTM standard at the time of writing. Over time, newer versions will exist. To access the latest version of an ASTM aircraft certification standard, follow the links below and then observe, if on the linked page the ASTM standard is labeled as “Historical” or “Active” (the latter will be with a green background box). If it is historical, go to the Version drop down menu in the gray box on the right of the page and select the most recent version. Once you make the appropriate selection, a new page will load with the latest version of the ASTM standard, marked as “Active”.