diff --git a/server/gameserver/room.cc b/server/gameserver/room.cc
index 44ca2e6..25adf3c 100644
--- a/server/gameserver/room.cc
+++ b/server/gameserver/room.cc
@@ -1274,7 +1274,7 @@ void Room::InitAirDrop()
 void Room::AirDrop(int appear_time, int box_id)
 {
     MetaData::MapThing* thing_meta = MetaMgr::Instance()->GetMapThing(box_id);
-    if (thing_meta) {
+    if (thing_meta && thing_meta->i->type() == 2) {
         a8::Vec2 dir = a8::Vec2::UP;
         dir.Rotate(a8::RandAngle());
         a8::Vec2 box_pos = gas_data.pos_new + dir * (500 + rand() % 300);
@@ -1305,6 +1305,13 @@ void Room::AirDrop(int appear_time, int box_id)
             box_pos.x = new_x;
             box_pos.y = new_y;
         }
+        if (box_pos.x + thing_meta->i->width()/2 + 2 > map_meta->i->map_width() ||
+            box_pos.x - thing_meta->i->width()/2 - 2 < 1 ||
+            box_pos.y + thing_meta->i->height()/2 + 2 > map_meta->i->map_height() ||
+            box_pos.y - thing_meta->i->height()/2 - 2 < 1
+            ) {
+            return;
+        }
         frame_event.AddAirDrop(appear_time, box_id, box_pos);
         xtimer.AddDeadLineTimerAndAttach(SERVER_FRAME_RATE * appear_time / 1000.f,
                                          a8::XParams()