I have been following the Persistent Surveillance System PSS [and similar] for quite a few years now and I really expected it to pop up in use at the London Olympics but no sign of it there. Whilst it does what it says on the label it does have this in-built problem of requiring a petty clear sky. Great in California but rubbish in most of Europe. That is possibly why it did not make London 2012. That is not a criticism - after all police aviation needs the same clear sky sometimes and is not therefore as persistent as the 24/7/365 hype tends to suggest.
The requirement for a PSS to need an endlessly orbiting aircraft suggests that it might get a bit boring up there and therefor perhaps once the technical side of Sense and Avoid is sorted its something a UAS could do.
On reading this article it seems that it is a fairly good back up to a modest coverage of CCTV [the ultimate 2012 London deterrent was lots of cameras] if targeting a specific area without the blanket application of ground cameras. But only of course while the Cessna carrier is in the air. How many PSS Cessna's would it need to cover LA all day every day? Impossible by any measure.
As I said PSS has been on offer for a long time now and new technology is appearing that might well just brush it under the table in the same way as those tape recorders were banished from airborne surveillance just when they got them right because someone 'invented' the solid state recorder in the same week
Harris now have a system that does the same thing without the requirement for the endless circling carrier aircraft. It is still in development but its a turret [about 15inch] that can be fitted to anything and as far as I can make out it changes the endless circling into an electronic scan to detect the changes. It will probably cost more but may be better.... especially if all it needs is to replace the EO/IR turret on your standard airframe.
They call it CorvusEye 1500 and ... maybe.
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