MacBook Air wifi NIC: supported channels
The manuals for all Air are stored online at http://support.apple.com/manuals/#macbookair and it looks like the latest Air is certified under the EU and Russia - but I don't see a good way to know precisely which channels are supported from a pre-sales or reference.

You can however, open your System Information utility and select Wi-Fi. It should show you the current Locale, Country Code and supported channels for your network adapter.