Fresh Lion install on a MacBook Air (Late 2010) without Recovery Key
Using ISO

If you restore the ISO to a flash drive or other drive partition, you could ⌥ alt-boot from it and erase &amp; install OS X.



In my example I selected a random DMG, however in your case you would use the ISO image as the Source.

Internet Recovery

Yes, but only if you install the Internet Recovery firmware update for your MacBook Air.

Once you have, hold ⌘ cmd + ⌥ alt + R on boot to begin.



An image of OS X will be downloaded from the internet, and can be installed normally.