--- a/src/clear_cmd.cpp	Sun Oct 14 19:57:15 2007 +0000
+++ b/src/clear_cmd.cpp	Sun Oct 14 20:12:51 2007 +0000
@@ -480,7 +480,7 @@
 	if (!CheckTileOwnership(tile) && _current_player != OWNER_WATER) return CMD_ERROR;
 
 
-	if (!EnsureNoVehicle(tile)) return CMD_ERROR;
+	if (!EnsureNoVehicleOnGround(tile)) return CMD_ERROR;
 
 	if (flags & DC_EXEC) DoClearSquare(tile);