So, in this week, I created a big airship with a landing strip, a biplane, and a bomb refueler (the biplane have magnet to attach bomb) but the problem is:
-my airship didn't fly stable (the Cot slightly behind the CoM)
-when I use gyroscope, the plane become unstable
-my plane can't take off (the plane usually not run in the straight line)
-size of the airship Soo big for my phone to handle (I can't even open the information button).

So anyone can help me to fix it? Or anyone can give me a suggestion? Thank you very much :D