Originally Posted by
msbbarratt 
And if RR has exploited this fit-in-a-jumbo characteristic to enable fancy deals with airlines buying the engine, what happens when (a long time in the future) the 747 freighter stop flying?
The big GE engines have a readily removable fan module that can be removed or installed in less than a shift, no special tooling required. Sure, they can go into the AN-124 intact, but it's not that big a deal if a -124 isn't available and it needs to fit in a 747F.
BTW, you do know that Boeing is still building new 747-8F, and remain convinced that there will remain sufficient demand to make it worth while to keep building them for many years. Many of the 747F currently flying are getting pretty long in the tooth - well over 100k hours (especially the freighter conversions - most were pretty high time before they were converted to freighters) and Boeing sees them getting replaced with new 747-8F before too much longer...