Mr Google At Work ?
 

Piper PA-31 Navajo VH-TSO looks to be doing a Google like photo mapping operation this afternoon. Starting south at Port Hacking, the aircraft has gradually
moved northwards, tracking east-west in passes 17nm long, and one nautical mile apart (from the western suburbs to just off the coast). The operation has
been performed at 15,500ft and 167kts, and departed Bankstown Runway 11L.

http://www.16right.com/MessageBoard/...eration 01.JPG

I'd more likely think it's doing NearMap stuff (they tend to update their maps quite regularly, the last one published over the airport was on September 11). It was out doing basically the same flight path a week or so ago too.

VH-TSO is continuing east-west passes this morning (today they are approximately 42 nautical miles long), starting just north of Manly and gradually moving northwards, picking up where it finished yesterday afternoon.

How long would a flight like that take?

Matt,

The run in the image above was 2 hours 50 min, and the run the next day on the northern side of the harbour was 2 hours 15 min.

A good scenic flight over Sydney

Full Details for VH-TSO flights on the 29th & 30th November.

NearMap has been updated, and is now showing the 29th November as the most current map.