There are 11 Fairchild KR-21 aircraft on the U.S. registry that TailWiki has a page for. Every one is built from the public FAA record — year, serial, engine, home base, and registration history — and owners and pilots add photos, trips, and stories on top. The ones listed here were built between 1929 and 1930.
N107M
1930 Fairchild KR-21
Independence, OR
N202V
1930 Fairchild KR-21
Orlando, FL
N207V
1930 Fairchild KR-21
Cincinnati, OH
N209V
1930 Fairchild KR-21
Sonoma, CA
N230V
1930 Fairchild KR-21
Somers, CT
N235V
1930 Fairchild KR-21
Oklahoma City, OK
N236V
1930 Fairchild KR-21
Klamath Falls, OR
N362N
1930 Fairchild KR-21
Cross, SC
N962V
1929 Fairchild KR-21
St Louis, MO
N204V
Fairchild KR-21
Ottumwa, IA
N206V
Fairchild KR-21
Cranbury, NJ