Finding Things Underwater
I am not an Aviator (Ianaa). However, I have spent many years trying to find long tubular objects underwater. First of all you need to know that every military naval vessel does a BT drop at least every 24 hours. These drops allow plotting of convergence zones for the local area. So, if I were for looking for a known frequency at a known signal strength at a known depth (the bottom) at a datum that I might have, the first thing I would do is deploy a device away from my ship. Why? Surface vessels pretty much suck at trying to find subsurface targets because they are too noisy. So using a PIB is a good idea. Get away from the ship and try some soundings based on convergence zones that may be calculated on a known datum. So, while it may seem crude, I thing the Chinese are being innovative with the equipment they have available. Regarding the posturing, the guys and gals that are doing the search are working to the best of their professional ability. The posturing happens at the High Command/Political level. The folks on the aircraft and the ships are just doing their jobs to the best of their ability.