The aircraft was a RR powered B767 and, as has been previously reported, they are more prone to tailstrikes than the GE powered aircraft. There was a quartering tailwind (NE) at the time (using RWY 16R) which is the optimum conditions for a tailstrike. The controllers in the tower observed the strike and reported it to the aircraft - the crew may have already been aware as they most probably got a "Tailskid" EICAS message. The subsequent runway inspection found the impact point but no debris so it's probable that the Tailskid touched (as it's designed to do) but the fuselage remained undamaged. The aircraft landed back on 16R approx 15 mins later, just after the inspection was completed.