In response to a few of the posts above, here is a summary of BTO characteristic:

http://www.atsb.gov.au/media/5187038...et_dec2014.pdf

There is a full technical document I remember reading somewhere but I can't find it right now, I'll search my HD to post if people interested. Basically it goes into math of the "cone intersecting a sphere" that gives the arc.

Now even if the arc was exactly right, and modeling the flight path from last known arc, there is additional sea drift components etc. It will be found, but may take a while!