PM From Germany, joined Feb 2005, 7109 posts, RR: 63
Reply 2, posted (9 years 10 months 3 weeks 1 day 22 hours ago) and read 1396 times:
They bought (or in some cases leased) their 747-400s new and selected the CF6 over RR or PW engines. The 747-200s with RR engines were second-hand and came from Cathay and Air New Zealand. Previously, they had operated still older 747s from SIA (and others?) with PW engines.
So the answer really is that their second-hand 747-100s and -200s came with whatever engines the original operator had selected but their new 747-400s have the GE engine that Virgin chose.