Combining the reported initial position of the wreckage with the best estimate for the flight path, MH370 impact would have been near 38S, 90E.

The distance from that position to Bermuda is 9525 nautical miles. The bearing from Bermuda: 112. Using sound velocity in water values calculated for the Heard Island experiment to Bermuda (4925 f/s), the sound travel time for any MH370 water-impact-generated signal to Bermuda would have been about 196 mins.

If the MH370 flew at the normal cruising altitude of 35,000 feet and the normal cruising speed of 550 mph for the estimated fuel remaining after turning left, it could have remained airborne for about 5.5 hours and covered a distance of about 3000 statute miles. The distance from the point of the left turn to the estimated impact position is about 3240, so we are in the ballpark.

The departure-from-the planned flight path turn occurred at 0120 Malaysian time (+8 hours) or 1820 GMT which suggests time of impact was about 0000GMT, the start of the new day 8 March.

Unfortunately, you would have to move the impact site to 43S, an additional 345 statute miles south to provide a deep water transmission path to the western Atlantic. Bearing 112 from Bermuda cuts through southern Africa.

I leave it to others to do the calculations for other sensor locations in WESTLANT using the map option at
http://www.movable-type.co.uk/scripts/latlong.html.