Worked in Manila with 3 JT9 engined 747-200 - 2 with 7Q,1 with 70A from 1988 to 1992 - 48 months, 53 engine changes!! We averaged 1600 hrs per engine and basically we changed all the engines every 3 months - The last wet lease GPA ever did,I think they must have lost a great deal of money on that contract.