หน่วยบนสลากกินแบ่งรัฐบาล สูตร1 งวด 1มิถุนายน2562(เข้า5งวด)
When flying a high-performance sleek aircraft often it is problematic getting the aircraft slowed down. Many super high performance aircraft and gliders have spoilers or speed brakes to help slow them down for landing by increasing drag.
from: http://ezinearticles.com/?Aircraft-Lighting-System-Fuel-Saver&id=78164
