This is a general UK rule set, based on CAP371 with certain assumptions. The following rules are checked:

• Max 3 consecutive early starts, late finishes or night duties
• Max 4 early starts, late finishes or night duties in any 7 consecutive days
• Max 5 early starts, where each duty is no more than 9 hours
• Max 7 days duty before a day off, allowing positioning on day 8
• 2 consecutive days off required in any 14-day block of duty
• 7 days off required in any rolling 4-week block. The week starts on the day as defined in preferences

It should be noted that there are several places in CAP371 where the regulations specify 'Operator to insert value here' or similar. In these cases, sensible assumptions have been made, but there is no guarantee that these will match your particular circumstances.

The limitations have been interpreted from the perspective of an airline and certain sections (applying to helicopter crew, for example) have been ignored.

Note that certain circumstances may not be included in the checking process, and it remains the pilot's individual responsibility to ensure their compliance with the regulations.