If it's smaller than standard-size, airport security doesn't need you whipping it out.
If you've travelled anywhere going through an airport, you'll know that the security scanning procedures now demand that you take your laptop out of your bag and place it in a plastic bin so that it can be scanned separately.
According to CNN's talk with a Transportation Security Administration spokesman, however, the 11.6-inch MacBook Air, along with the iPad, do not need to be removed for your baggage when undergoing scanning.
One early adopter of the iPad who went through airport security said that she was told that her Apple tablet didn't need to be scanned separately because it "doesn't have a CPU or hard drive."
Of course, the MacBook Air doesn't have a hard drive either, instead relying on solid state storage. It does, however, have a CPU – albeit an old one. But that's not the official reasoning from the TSA.
The reason that the 11.6-inch MacBook Air can stay in your bag is because it is "smaller than a standard-size laptop," which puts it in the same category as netbooks.
Despite having nearly the same internal design, the 13.3-inch MacBook Air doesn't get the free pass and must be removed from one's bag.