My understanding is that these engines (GEnx for certain), are being developed for thrusts up to 75 000 lb, and with the A350 "growing" all the time, it's likely that they will actually get built at this thrust, if not higher.
It seems to me that this places these engines squarely in the thrust range for the A380 - even the possible 590t-600t HGW version.
Others on the forum may help me on this one, but I would guess (and it is a guess) that GEnx/Trent 1000, with higher BPR, slower turning main fans (for Trent for certain) etc. etc would be 3% - 5% more efficient than even the relatively recent Trent 900/GP7200 engines currently on the A380.
Being 112" fans as opposed to 116" fans they will also be lighter, and have less drag on the wing.
How difficult would it be to certify these engines for the A380?
Would this be a sensible thing to do?
Would it be too costly?
If my guesses are anything like near the mark, these engines could increase the range of the A388 from c8000 miles to c8400-8500 miles - a considerable improvement.
Possibly an even greater benefit, though might be complete commonality with the A350 for fleet decisions (a benefit shared by the 787/747ADV)
On a lighter note, if the A388 could reach 8500 miles or so with these engines, it might open the way for the A388 HGW version to challenge the 772LR for the title of the world's longest range aircraft.
550 passengers and 9500 miles - all the plane you'll ever need.......
Seriously, though, would this engine certification be a sensible consideration for Airbus, or is it just pie-in-the-sky from my fertile imagination?