I saw this on the 07R take off roll a couple of weeks ago, seemed to be coming from the other end of the runway out to the right. I looked it up on google earth and assumed that it must have been kids at the park that seems to be just next to the airport. What an awful system. Other chap didn't see it, it was only brief but distracting nonetheless. I couldn't be sure if this was the bird dispersal system or just a local idiot. Not impressed eitherway.