อ.เชตุพล | วิเคราะห์เลขเด็ด ซองดัง 2/พ.ค./2562
To prevent severe vibration or flutter of flight control surfaces during flight, design balance limitations must be observed when carrying out flight control surfaces repair. Retaining proper balance and rigidity of flight control surfaces is critical.
from: http://ezinearticles.com/?Flight-Control-Surfaces-Repair&id=5693306
