This question applies to Classic Traveller (Books 1-3) designs.
I've been running the numbers for confirmation on some ship designs
that have been submitted, and I'm a bit confused all of a sudden. If I
look at the example ships from Book 2, the fuel tankage quoted seems
to be exactly what's needed for the specified Jump capability, but is
cited as "supports _n_ Jump _m_ and four weeks of operation". Is four
weeks of Power Plant/Maneuver fuel included in the allocation for the
Power Plant? If so, how do I determine how much fuel to add if I'm
designing the ship for extended-duration operations? If Power Plant
fuel is considered to be part of the cited fuel allocation, then how
can a 400td hull with J1 capability support 3xJ1 plus 4 weeks on 120td
of fuel?