diff --git a/src/aircraft_cmd.cpp b/src/aircraft_cmd.cpp
index 12315894e9..d363fd3d40 100644
--- a/src/aircraft_cmd.cpp
+++ b/src/aircraft_cmd.cpp
@@ -998,7 +998,7 @@ static bool AircraftController(Aircraft *v)
 			/* Turn. Do it slowly if in the air. */
 			Direction newdir = GetDirectionTowards(v, x + amd->x, y + amd->y);
 			if (newdir != v->direction) {
-				if (amd->flag & AMED_SLOWTURN && v->number_consecutive_turns < 8) {
+				if (amd->flag & AMED_SLOWTURN && v->number_consecutive_turns < 8 && v->subtype == AIR_AIRCRAFT) {
 					if (v->time_counter == 0 || newdir == v->last_direction) {
 						if (newdir == v->last_direction) {
 							v->number_consecutive_turns = 0;