You are entitled to a subsistence allowance when flying out of your assigned HOME BASE.
To claim this go to the Expenses, Travel & Subsistence link and click the Daily HOME BASE subsistence tab. Here you will find the instruction on how to claim your DAILY HOME BASE subsistence.
Alternatively you can also uplaod your roster using the roster link on the website. THis will automatically calculate the DAILY HOME BASE SUBSISTENCE for your whole roster and then you can submit it by pressing the submit expense button.