On Sun, 2 Jul 2017 17:48:36 -0700, you wrote to Freelance Traveller:

>On Sun, Jul 2, 2017 at 5:35 PM, Jeff Zeitlin <xxxxxx@freelancetraveller.com>
>wrote:
>
>> 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?
>>
>
>Jeff, I just reread the 77', 81' and TTB descriptions, all of them have
>aprox. 220 tons of fuel. But all have around 120 tons of Cargo.

No, B2/1981 shows the 400td Patrol Cruiser shows 120 fuel:

>Patrol Cruiser (type T): Using a custom 400-ton hull, the patrol
>cruiser is a military vessel used for customs inspections, piracy
>suppression, and normal safety patrols. It has jump drive-F, maneuver
>drive-H, and power plant-H, giving the ship performance of jump3 and
>4-G acceleration. Fuel tankage of 120 tons supports the power plant
>and allows one jump-3. Adjacent to the bridge is a Model/3 computer.
>There are twelve staterooms and four low berths. There are four triple
>turrets installed, with fire control; two mount lasers and two mount
>missile racks. A GCarrier and a ship's boat are carried. There is a
>50-ton cargo bay, and the ship is streamlined.
>
>The patrol cruiser has a crew of 18: pilot, navigator, three
>engineers, medic, four gunners, and eight troops for boarding parties.
>Double occupancy for the gunners and troops is required. The ship
>costs MCr221.04 and takes 14 months to build.

Extracting the relevant line:

>                  Fuel tankage of 120 tons supports the power plant
>and allows one jump-3.

Recalling (and confirming from the book) that Jump Fuel is (disp * 0.1
* jump), the required jump fuel for the Type T is (400 * 0.1 * 3), or
120. Which is the cited fuel tankage. And yet it supports the Power
Plant as well. For zero fuel? Ummm... No. Not when there's a formula
that PP fuel is 10*Plant Rating. So for a power plant whose rating in
a given hull is '2', that means 20 tons. Note that I can't actually
find the cite for "four weeks", but that seems to be the Core
Assumption.

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Freelance Traveller
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xxxxxx@freelancetraveller.com
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