There are 21 Air Tractor AT-400A 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 1979 and 1987.
N73127
1987 Air Tractor INC AT-400A
Vernon, TX
N73006
1985 Air Tractor INC AT-400A
Hayti, MO
N7307W
1985 Air Tractor INC AT-400A
San Francisco, CA
N73085
1985 Air Tractor INC AT-400A
Walnut, IL
N497GA
1984 Air Tractor INC AT-400A
Canton, SD
N3160X
1983 Air Tractor INC AT-400A
Walnut, IL
N23813
1982 Air Tractor INC AT-400A
Bellevue, TX
N2394N
1982 Air Tractor INC AT-400A
La Salle, CO
N331KE
1982 Air Tractor INC AT-400A
Eaton, CO
N4350J
1982 Air Tractor INC AT-400A
Nickerson, KS
N23416
1981 Air Tractor INC AT-400A
Walnut, IL
N2347P
1981 Air Tractor INC AT-400A
Huron, SD
N3650D
1980 Air Tractor INC AT-400A
Walnut, IL
N3655B
1980 Air Tractor INC AT-400A
Walnut, IL
N3657T
1980 Air Tractor INC AT-400A
Sauk Centre, MN
N3658T
1980 Air Tractor INC AT-400A
Pelkie, MI
N8791S
1979 Air Tractor INC AT-400A
Walnut, IL
N8907S
1979 Air Tractor INC AT-400A
Walnut, IL
N23951
Air Tractor INC AT-400A
Raymondville, TX
N3157B
Air Tractor INC AT-400A
Lamoni, IA
N400DQ
Air Tractor INC AT-400A
Nyssa, OR