I'd like to ask all to keep a lookout for a Fairchild AT-21 Parts catalog, AN 01-115KA-4.... I finally found a copy last year, but it's missing from page 372 on. It's probably only about 12-14 pages, but those pages have the rest of the standard parts listing and the special tools. I've exhausted all my normal sources, NMUSAF at Dayton doesn't have a copy, same with all the known manual dealers. NASM might have a copy, but there is something like 1200 boxes of Fairchild stuff that they hold and only cursory inventories are available online for about 850 of those boxes.