The following graphic was compiled from photographic evidence available from
images.defence.gov.au and shows the 5 x 8km (40km2) search grids laid out on a transverse Mercator projection, along with the #1 ping, #1 LOS and #2 ping detections made on 05 April 2014.
I know that JACC have stated the search area was centred on the 2nd ping detection of 08 April, but the evidence is to the contrary, with Ocean Shield AIS position reports clearly backing up the above content. In fact the OS was working in C11 prior to diverting to Geraldton, WA, and on return was working in E11.