# Четыре основные силы, управляющие полетом самолета

- Author:
- Михаил Алферов, Chris Mantolas

Нажмите на кнопку воспроизведения (нижний левый угол)), pause on points, zoom in and see the forces by clicking on Check boxes!! Be careful to choose the right angle with sliders on each point. Check the whole explanation step by step to the bottom of the page!!!!

Check out all the steps.
1st : This is the whole route of Spitfire
2nd : The aircraft is on equilibrium. There are two basic forces. There is a total Reaction acting on the wheels of spitfire from the ground and also the total Weight from the mass of the aircraft and the pilot. (Rt –Wt=0).
3rd : On the third step wich is exactly before lift up all the forces of the airplane have been appeared. Total Reaction disappears because is zero.Thrust is greater than drag while lift is greater than weight.
4th: On the fourth step forces are like the previous image(Thrust>Drag ,Lift>Weight). The basic change is that now the elevators and ailerons are upwards and spitfire has the right angle, the angle of attack (=16˚).
5th: Now the aircraft is travelling at rest. That means that all the forces are equal. (Ftotal=0)
6th : Here the pilot decides to land. He reduce the power of engine(Thrust). As a result, the speed reduces because Drag > Thrust. Also he moves the elevator downwards and the nose of spitfire goes down (12˚). Consequently, the whole aircraft goes down (Weight > Lift).
7th : Finally spitfire lands on the airfield with the right angle and the right speed.