Ce trebuie să știi

This is a fascinating fact file and learn-it-yourself project book. It is an accessible and lively introduction to every aspect of flight, including wings and lift, air resistance, gliding and soaring, in both machines and the animal kingdom. It features 18 hands-on experiments to help you really find out for yourself - make a miniature plane and a hot-air balloon, construct a kite, and build models to demonstrate how birds fly and how jet engines work.