http://www.thestar.com.my/News/Nati...an-Ocean-for-several-more-days-trying-to-pin/
Searchers will spend several more days trying to pinpoint a crash site
before a mini-sub is launched to scour the seabed.
They were on CNN a little bit ago and made some good points about using the submersible anyway. They have enough data already even if they dont get another hit on the pinger.
Here is the thing. There is a certain maximum range that the pinger locator can hear a ping. They indicated that it is up to 2 nautical miles away.
So lets assume the ship was at the furthest point away from the black box.
That would mean the ship was 2 miles away from the box. If you draw a circle with a radius of 2 miles in every direction around that ship, you now have the only possible spot for the box to be. This is the circle the submersible needs to map.
And if you want to play it safe, then just make the circle a little bigger.
So at most they would only need to have the submersible go down and map out a circle with a radius of 2 miles which is a diameter of 4 miles across.
To help get a square mile estimate you can just make a square with 4 mile long edges and you now know you have at most 16 square miles of ocean surface to map. That is very doable. Sure, it is a lot, but they cannot
ever say they dont have enough information to use that submersible.
The only reason that submersible would not find that black box is if the pinging noise was something else like a submarine making an inadvertant noise that was 1 second apart. It does seem very fishy since the Chinese ship also detected a noise 300 miles away.