Answer: To boost its acceleration because the Earth rotates Eastwards and to ensure that any crash will occur on an ocean and huge loss in life and properties will be averted.
Explanation: A space shuttle turns to the east as soon as possible,this is to ensure that the space shuttle acceleration is supported by Earth rotation which is also Eastwards.
Another reason for ensuring that the space shuttle turns Eastwards as soon as possible is to prevent a huge loss of life if there is any chance of crash by the space shuttle.When the space shuttle turns Eastwards it will ensure that any crashing will possibly be on the an ocean hence a huge loss of life an property in populated areas will be averted or reduced.