The JP8 sounds better than JP4, now that I think about it.
But I was fairly certain that the initial design was to carry _two_ Abrams.
The only
source I have handy gives a maximum combat payload of 291,000 lbs.
The
M1A2 Abrams MBT' comes in at 68. 7 tons, or 137,400 lbs. Two of them comes to 274,800 lbs, leaving about 8 tons of useful payload left.
Don't have any figures for non-wartime payload, but max gross weight is about 71,000 lbs less.
I'm guessing that's the difference in our figures. Under non-combat conditions, (whether because of civil airspace regs, or attempts to limit airframe fatigue) the load rating is not sufficient to carry two of these tanks. But when a war breaks out, they can fit two of 'em.
My data's half a decade old, though, so they may have downlined that rating since then for safety reasons.
Still, 440 tons max gross is pretty big, either way

.
--Ty