Originally Posted by
stilton
Eastern had RR engines from day one on their 757s, they did modify them to a higher thrust, more efficient version with a different, extended cowling a few years later as did BA, the other launch customer
BA kept the original 535C engines on their 757s that were delivered with them. G-BIK* and G-BMR* series aircraft.
BA’s later G-BPE* and G-CPE* aircraft delivered from 1989 had the E4 engines. But BA never converted an aircraft, and continued to take delivery of the C engines long after the E4 was available.
Eastern converted all their C powered 757s. As did Monarch. The only airlines to do so as I recall. Air Europe never changed engines on their few early C powered 757s.