You are misunderstanding the meaning of those arcs.
They represent an approximate maximum distance from the receiver, but absolutely nothing else.
In fact, if you draw the line from the receiver to the 8:11 position on the arc, it is strong evidence that the flight ended somewhere along the border between Pakistan and Afghanistan.
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>>They represent an approximate maximum distance from the receiver, but absolutely nothing else.<<
No, you are misunderstanding the meaning of those arcs. They indicate that, at 8.11, the plane was located on the arcs somewhere, but that’s it. It has nothing to do with “maximum distance from the receiver” and everything to do with “approximate distance from the satellite.” In other words, it’s not a maximum distance, it’s a more or less exact distance from the satellite (or receiver as you call it). And it would be very difficult to land the plane in Pakistan before 9.11 from that distance, even assuming it were anywhere near the northern part of the upper arc at the time.
In fact, the searchers seem to have enough information to be concentrating on the southern arc in the Indian Ocean instead.
>>n fact, if you draw the line from the receiver to the 8:11 position on the arc, it is strong evidence that the flight ended somewhere along the border between Pakistan and Afghanistan.<<
There is no apparent reason to draw a line from the satellite’s position toward Pakistan. There is, in fact, no 8:12 position on the arc. The entire southern and northern arcs describe the approximate location of the plane as being somewhere along those arcs. Nothing on the picture justifies assuming the plane is any closer to Pakistan than to the South Indian Ocean.
That statement tells me that you don't know diddly squat. The plane was not flying from the satellite.
The 8:11 arc depicts the places the airplane could have been at 8:11 Kuala Lumpur time. The question then is, starting from a point on the 8:11 arc, could it have made it to Pakistan before time to draw the 9:11 arc? Parked and powered down (or crashed) — mustn't talk to Inmarsat again!
The shaded area on the map I posted represents the places it could have flown with one minute to spare before the next satellite ping.
The ping arcs are calculated the absolute, not the maximum, distance from the satellite to the airplane.
The satellite cannot sense direction. But, by measuring the ping return time, it can estimate the distance from itself to the airplane. That defines an imaginary sphere in space, which intersects with the earth's surface at the possible locations of the airplane at the time in question.