How can I see the revision history of a particular FAR?
Changes to federal aviation regulations are listed on the FAA’s Regulatory &amp; Guidance Library (RGL) at http://rgl.faa.gov/:


From the home page, click on the database titled "Code of Federal Regulations"
On the left, in the navigation tree, select one of the branches under "Historical CFR" (for example, "By Part")
On the right, expand the items leading to the regulation that you are looking for (in this case Part 61)
Scroll down to the regulation that you are looking for (61.51) and it will list the original version and all of the revisions:




Each revision is a link which takes you to the regulation as of that version, with links to the NPRM's and dockets so that you can see what has been changed!