Whenever one of the local days prescribed by Clause 9, Directive No 2000/79/EC, is assigned as a single day, it must contain two local nights. Whenever consecutive local days are assigned, the last day may not contain a local night. However, from a fatigue management perspective, planning the last day to end at midnight, reduces the restorative effect of that last day to a minimum. Rising before midnight to report at 00:01 on the last day could generate sleep debt.
The term ‘single day free of duty’ has been included in Regulation No 965/2012 in order to enable the implementation of Directive No 2000/79/EC, in particular its Clause 9:
Without prejudice to Clause 3, mobile staff in civil aviation shall be given days free of all duty and standby, which are notified in advance, as follows:
(a) at least seven local days in each calendar month, which may include any rest periods required by law; and
(b) at least 96 local days in each calendar year, which may include any rest periods required by law.’
Clause 9 above employs the term ‘local day’ i.e. a period of 24 hours finishing at 00:00 LT. At the same time, a ‘single day free of duty’ is a period of one day, including two local nights, that may finish between 06:00 and 08:00 LT, depending on the local night start and end times.