The RDR-1F Wx radar in the ANZ DC-10 fleet would paint only a thin line when presented with a steep mountain from 1500 feet altitude. It would have been useful before they descended, however.
GB
I believe that ice absorbs radar waves and that ice covered mountains would not show on older airborne weather radars. I vaguely recall this point was made during the original investigation. If correct, it would suggest that relying on weather radar for terrain clearance in the Antartic is risky.