guys nobody out here is actually answering my question.
My question was "Why is aircrafts momentum, size and shape not taken in consideration while determining drift angle"
can some one please give me a simple explanation.
Different question than in the original post.
Momentum (mass/speed), size, shape are only factors when the forces acting on the object change.
You can take a few physics courses at university to get the complete explanation, in order to understand static and dynamic forces, but I'll try to give a brief explanation.
Acceleration (or deceleration) in any direction is affected by Mass (weight), but an object that is at a constant Speed has no acceleration, so Mass is not a part of the equation.
The force equation is F=MA where F is force, M is Mass, and A is acceleration.
Speed is calculated as V=D/T where V is velocity, D is distance and T is time.
When speed is to be calculated as a result of acceleration, V=Vo + AT where Vo is the initial velocity, A is acceleration and T is time.
If the forces on a aeroplane change (wind speed or direction changes or power changes or control changes), then the speed (and thus ground track) will change and this change will be a factor of Mass.
However if the forces do not change, then the ground track (Velocity) will NOT be affected by Mass (weight)
In a moving wind-mass (block of wind) the if the aeroplane were 'stationary' in the wind it would be travelling the same speed and direction of the wind.
To make things simple, let's say that the wind is blowing toward 090 at 20 knots.
And to continue to make things simple, let's say the plane is pointed 000 and is travelling at 100 knots.
As the plane moves toward 000 at 100 knots within the block of wind it is also moving toward 090 at 20 knots as a result of the wind moving across the ground.
Weight doesn't come into it at all.
If the plane weighs 1000kg it will be going to 000 at 100 and to 090 at 20.
If the plane weighs 9999kg it will be going to 000 at 100 and to 090 at 20.