[ProtectOurFreedom]

Airliners take off with sufficient fuel to reach the destination plus a reserve for diversions. Somebody wrote that there is extra reserve at night. But they aren’t fueled to max if the destination isn’t at max aircraft range. So the radius probably doesn’t include Somalia.

[Professional Engineer]

But they aren’t fueled to max if the destination isn’t at max aircraft range. So the radius probably doesn’t include Somalia.

Assuming the fuel guy didn't top it off for an extra couple of yen.
/tinfoil

[NELSON111]

This isn't assuming they were fueled to the max. This figure assumes they flew for 6 hours after they disappeared since it is said they had 7.5 hours of fuel on board (assuming no ground crew conspiracy which gave them more).

A fully fueled 777 would have gone MUCH farther than Somalia. Again...the range I gave just assumes a range of 6.5 hours from where they were last seen.