AA have Trents on their 777's
They have to go wrong sometimes
Speaking of low loads and NRT. I once flew out of there on Jan 1st at 11am on BA.There was 1 in F, 3 in J and 41 down the back.
It was my "pre" honneymoon and we got the upper deck all to ourselves. Its very quiet on a 747 with just 45 paxs