Minimum fuel for a 13hr sector is in the region of 120T, so with a MZFW of 237T, they will definatley be payload limited to the tune of 37 Tonnes!!
DOWs are usually around 175, so that leaves them with the the princely sum of around 25T payload.
Our 15 hr SFO flights in a 300ER are restricted to about 220T ZFW
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