To remove a pilot/user from your list of active pilots, go to the Admin | User Mgmt and select the user. Once the user is selected, click the status tab. There you will find a link for retiring the user or checkboxes for suspending them. If the user has schedules, the schedules will be canceled when the user is retired. (Users can not be removed - only retired or suspended.)
If you need to remove several inactive users (that have not scheduled recently), you may want to use the 'Bulk Retire' function, which is Admin | User Mgmt | Retire/Suspend.
Note: Do not reuse accounts, since reports and historical data tracks the user #. Instead, retire inactive users and assign new spare users as needed. We do not charge for retired or inactive users.