Quote from 777fly:
Unless a top of climb routine or scan is carefully done to include the radar tilt setting, it is all too easy to leave the tilt at the takeoff setting and see nothing but clear sky on the radar display.
Can't see any experienced (on-type) crew making such a fundamental mistake, even if more than one spec. of radar was installed on the fleet. You always check frequently for surface returns, adjusting the tilt to suit. If there are none (smooth water), you will be on your guard. These guys knew where the "F.I.T." was, and they had presumably flown southbound a couple of days earlier.
Chris