Before Inmarsat tells us how good it is at tracking planes, it needs to release its raw data and explain how they arrived at that flight path to the current search area.
Their graphs of the arcs and flight paths don’t seem to match their numbers or the search area.
They claim that the plane averaged 375mph from 3:11 through 8:11 — that’s 1875 miles over 5 hours.
But its graph indicates its speed to have been about 500mph from 3:11 through 5:11 on primarily a north south axis before turning east south east.
If it flew 1000 miles south during those 2 hours then it only needed to fly 875 more miles to reach where it ended up at 8:11.
875 miles from there is Christmas Island just south of West Java.
So then why are they looking 700 miles south of there???
Inmarsat arcs here:
http://www.freerepublic.com/focus/bloggers/3135643/posts?page=28#21
Note on the chart how far they have the plane flying from 3:11 to 5:11 — that’s a distance of about 1250 miles over 2 hours @ 625mph.
That’s not possible since it’s max speed is about 550mph and it was travelling before that at about 450mph.
From that point to where they are searching is then about 1035 miles — that’s an average speed of about 345mph.
If they would correct the 3:11 to 5:11 speed and distance they would find that the plane intersected the 8:11 arc about 500 miles north closer to Christmas Island.