Spotting on the West runway (17-R/35-L) is possible but isn't very exciting in my opinion. From the official viewing area you can see aircraft arrive and depart on the East runway as well as aircraft on the West runway (although far away, you can still tell what they are). You also can see aircraft taxi and all the aircraft at the gates.
On the North end of the West runway (17-R) you will see planes approaching that runway and that is it.... no touchdowns no taxiing and no departures.
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Photo © Jason Knutson
On the South end of the West runway (35-L) you will see planes approach, touchdown and depart. I've only actually spotted at this location once due to the fact that it isn't very safe due to it's close location to a very busy road (Burleson Road).
Okay...on to the locations.
The spot at the North end of the West runway is a cemetary. This isn't a very obvious spot and I didn't know about it till a friend showed it to me. If you take Hwy 71 West towards Austin from the airport, exit on 183 South and immediately get into the left lane. Take the first cross over you come to and go across the Northbound lanes. A single lane road will lead between 2 fences and into a cemetary which is at the end of the runway. I'd suggest having a scanner or something to listen to here as it is pretty boring when there are no aircraft coming. If airplanes are landing from the South (common during the winter) don't even bother with this spot as the only thing you will see are airplanes flying over you at about 1000'.
To view from the South end (only good when planes are landing from the South). Continue South on 183 and take a left on Burleson Road (I think there is a sign that points to the General Aviation area just before this intersection). Not too far down Burleson you will see the end of the runway. I pulled off into the grass and sat for a while but didn't feel safe with all the traffic zooming by so I left and haven't gone back since.
The spot I use the most is the official spotting area as it has the most action. My second choice is the cemetary spot, especially when I'm trying to get photos of a cargo plane.
There are other areas where I've sat and watched planes for a while and all I'm going to say is to explore the airport. Go in the GA entrance and drive around. As long as you don't go behind a gate with the red warning sign on it, no one will say anything. I've been in places where I didn't see another car the entire time I was there and Aviation police would see me with my camera and wave as they drove by.
Now, here is my take. I like the spotting area on Golf Course Road. However, when there is a north wind, they approach over Burleson VERY close to you. However, I got heckled by the cops for spotting here. The spotting area is reasonable enough. I have seen AA and CO 757s in the morning at like 6 AM waiting for departure around 7 AM and at around 7 PM. So, you can have an opportunity to see them. Frontier is a nice, new airline flying A319s into AUS. I also saw Vanguard for the first time the other day and I like them. This was on Burleson around 5 PM. I have also seen Champion 722s and Transmeridian 722s, but they are rare. Also, when there are storms in Houston, loads of CO heavies come in. Also, what kind of camera did you buy?