diff --git a/aircraft_cmd.c b/aircraft_cmd.c
--- a/aircraft_cmd.c
+++ b/aircraft_cmd.c
@@ -362,7 +362,7 @@ int32 CmdBuildAircraft(TileIndex tile, u
 		v->service_interval = _patches.servint_aircraft;
 
 		v->date_of_last_service = _date;
-		v->build_year = u->build_year = _cur_year;
+		v->build_year = u->build_year = _cur_year - BASE_YEAR;
 
 		v->cur_image = u->cur_image = 0xEA0;