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As it's not a unit meant to be replaced by the user: yes. Might turn out good, but why take the risk?
 
Does replacing the hard drive in a Macbook Air void the warranty?
Yes. As stated in the booklet that came with your MBA, entitled, "Congratulations, you and your MacBook Air were made for each other."
Your MacBook Air does not have any user-serviceable or user-replaceable parts.
 
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