On first glance my answer would be "no" because if there's no drive hooked up, there's no way to read a disk on the computer, right? Wrong.

What I remembered after a bit was that when you've more than one Apple Mac connected via a local network, you see each drive on the remote system not just the system itself. Stands to reason, actually.

In this situation, though, it's going to be a good thing: what you need to do is connect your Dad's MacBook Air up to another Apple Mac that does have an optical (CD/DVD) drive and use that remotely.

Let me show you how it works...

First off, my favorite way to connect to another Mac on the network is to use the Command-K shortcut. When I press those keys, here's what I see:

The "Time Tunnel" is my network backup device, and the G5 Desktop is the device I want to share, a desktop computer in my office.

When I connect to it - entering the proper password, of course - I can see each of my drives (X and X2), my home directory and the CDROM I've inserted into the desktop optical drive, "Monopoly":

Sweet! Double click on the CDROM name and:

It's just like browsing the disk directly. When I'm ready, I'll do what it suggests and drag the specified folder directly from the remote optical drive to my local Applications directory:

It'll copy...

and after a minute or two, success!

Software installed exactly as it would have been if I'd have had an optical drive directly on my own MacBook Air (though perhaps just a wee bit more slowly).